KR20010083041A - Methods and apparatus for confocal interference microscopy using wavenumber domain reflectometry and background amplitude reduction and compensation - Google Patents

Abstract

An in-focus image of the region above and / or within the object 112 generates a reference beam R22B from the probe beam P22B and the broadband point source 90 and produces an asymmetric spatial feature in the reference beam R32B Focus return beam, and generates an asymmetrical spatial property in the in-focus return probe beam P32B by converting the probe beam into an in-focus beam in the area, generating an in-focus return probe beam, Of-focus image in order to reduce errors in the image. The in-focus return probe beam is then spatially filtered (P42A) and passed through the dispersive element to focus it (P42C) onto a line in the detection plane of the detector system 114. [ The reference beam is spatially filtered (R42A) and travels through the dispersive element to focus it (R42C) onto the line in the detection plane. The beam from the out-of-focus image point is spatially filtered (P62A) and advanced through the dispersive element (P62C). A reference beam R42C that is spatially filtered in the detector plane is incident on the beam spot P62C from the out-of-focus image point spatially filtered in the detector plane and the in-focus return probe beam P42C spatially filtered in the detector plane. Lt; / RTI > The amplitude of the spatially filtered in-focus return probe beam P42C is the interference term between the reference beam spatially filtered in the detector plane and the in-focus return probe beam P42C spatially filtered (R42C) in the detector plane Is detected by the detection system 114. The amplitude of the interference term between the amplitude of the out-of-focus image beam P62C spatially filtered in the detector plane and the amplitude of the spatially filtered reference beam R42C in the detector plane is thus spatially reduced and the image information of the object To reduce errors in the data processed by the detector system 114 to indicate < RTI ID = 0.0 > a < / RTI >

Description

[0001] METHODS AND APPARATUS FOR CONFOCAL INTERFERENCE MICROSCOPY USING WAVENUMBER DOMAIN REFLECTOMETRY AND BACKGROUND AMPLITUDE REDUCTION AND COMPENSATION [0002]

The present invention relates to a technique for making an in-focus image of an object or a cross-section of an object fast and accurate and to provide an out-of-focus method for statistical errors and systematic errors. -focus) The effect of the optical signal from the foreground and / or background light source is largely eliminated. Confocal and confocal interference microscopy can find many applications such as, for example, life sciences, biological sample research, industrial research, and semiconductor metrology. This is because the devices have a unique 3D imaging capability.

When multi-dimensional imaging is the most challenging, perhaps when the background of the out-of-focus image is significantly larger than the in-focus image signal. Thick samples, particularly those in which the confocal system is not in transmit mode This is often the case when operating in reflective mode.

In general, there are two approaches to determining the volume characteristics of a three-dimensional microscopic specimen. Both approaches are based on conventional microscopy and focus microscopy. In general, conventional microscopy approaches require more time to process data for a three-dimensional image, although less time is required to obtain the data as compared to the confocal microscopy approach.

In conventional imaging systems, when a portion of an object to be imaged deviates from an axis from an optimal focus position, the image contrast is reduced but the brightness is kept constant, so that out- Interferes with the field of view of the object in focus.

If a known point-spread function of the imaging system is known and an image of each independent portion of the object is obtained, then a known computer algorithm may be applied to the obtained image to produce out- Effectively producing an image containing only the in-focus data. The known computer algorithms are of various distinct types, referred to as computer deconvolutions, and generally require expensive computer equipment and considerable computation time and a significant amount of data to achieve the desired statistical accuracy.

The wide field method (WFM) uses a conventional microscope to successively acquire a set of images of adjacent focus planes passing through a volume of interest (D. Agard and J.W. Sedat, " Three-Dimensional Analysis of Biological Specimens Utilizing Image Processing Techniques, " proc. soc. photoOpt. Instrum. Eng., SPIE, 264, 110-117, 1980; D.A. Agard, R. A. Steinberg, and R. M. Stroud, "Quantitative Analysis of Electrophoretograms: A Mathematical Approach to Super-Resolution," Anal. Biochem. 111, 257-268, 1981; D. A. Agard, Y. Hiraoka, P. Shaw, and J. W. Sedat, " Fluorescence Microscopy in Three Dimensions, " Methods Cell Biol. 30, 353-377, 1989; D. A. Agard, " Optical Sectioning Microscopy: Cellular Architecture in Three Dimensions, " Annu. Rev. Biophys. Bioeng. 13, 191-219, 1984; Y. Hiraoka, J. W. Sedat, and D. A. Agard, " The Use of a Charge-coupled Device for Quantitative Optical Microscopy of Biological Structures, " Sci. 238, 36-41, 1987; W. Denk, J. H. Strickler, and W. W. Webb, " Two-Phon Laser Scanning Fluorescence Microscopy, " 248, 73-76, 1990). Each image was captured using a cooled charge-coupled device (CCD) image sensor (J. Kristian and M. Blouke, "Charge-coupled Devices in Astronomy," Sci. Am. 247, 67-74, 1982) and includes data from both the in-focus image plane and the out-of-focus plane.

The technology of laser computed tomography is implemented using conventional microscopes. [S. Kawata, O. Nakamura, T. Noda, H. Ooki, K. Ogino, Y. Kuroiwa, S. Minami "Laser Computed - Tomography Microscope," Appl. Opt. 29, 3805-3809 (1990)] uses a three-dimensional volume reconstruction rather than a two-dimensional slice reconstruction, although based on a principle closely related to the technology of X-ray computed tomography. The projected image of the thick three-dimensional sample is collected into an improved conventional transmission microscope with oblique illumination optics, and the three-dimensional structure inside the sample is reconstructed by the computer. Here, the data requires a short time when compared with the time required to process data for a three-dimensional image. In an experiment by Kawata et al., Ibic., An 80x80x36-voxel reconstruction requires moisture to collect all projections and sends the project to a minicomputer. At this time, at the rate of 20 milion floating point calculation (MFLOPS), even if a vector processor is used, approximately 30 minutes is required for digital reconstruction of the image.

In conventional point or pinhole-confocal microscopes, light from a point source is focused within a very small space known as a spot. The microscope focuses light that is reflected or scattered from the spot or transmitted through the spot to the pointer detector. Reflection Point - In a reflecting point-confocal microscope, the incident light is reflected or scattered by the sample portion in the spot. The light reflected or scattered back by the sample outside the spot is spread out because it is out of focus on the detector and the point detector will only receive a small portion of the reflected light or again scattered light. The transmitting point- confocal microscope, the incident light is transmitted if it is not scattered or absorbed by the sample portion in the spot. Generally, the point sources and point detectors are each brought close to each other by placing masks with pinholes in front of conventional detectors and conventional light sources.

Similarly, in a conventional slit-confocal microscope system, light from a line source is also focused into a very narrow, long space known as a spot. The slit-confocal microscope focuses the light reflected or scattered from the spot or transmitted through the spot to the line detector. The line source and the line detector are approximated by using a mask having a slit before a conventional light source and a conventional detector row, respectively. Alternatively, the line source is approximated by sweeping the focused laser beam across the object to be imaged or irradiated.

Since only a small portion of the object is imaged by the confocal microscope, in order to obtain sufficient image data to completely construct a two- or three-dimensional image of the object, the imaged object must move and the source and detector must also move . The slit-confocal system moves the object linearly in a direction perpendicular to the slit to obtain a continuous line of two-dimensional image data. On the other hand, a point-confocal system with only one pinhole must be moved in a two-dimensional manner to obtain a three-dimensional set of image data. The raw image data is typically processed and then processed into a three-dimensional image from a two-dimensional cross-section of the object to be illuminated and imaged. The reduced sensitivity of the out-of-focus image associated with conventional microscopes improves the statistical accuracy for a given amount of data and the processing operations are significantly simpler than when the processing data is obtained with a conventional microscopic approach.

In a system known as the Tandem Scanning Optical Microscope (TSOM), the spiral pattern of the illumination and the detector pinhole are etched into a Nipkow disk, The entire subject is scanned in two dimensions [cf. M. Petran and M. Hadravsky, " Tandem-scanning Reflected-Light Microscope, " Opt. Soc. A. 58 (5), 661-664 (1968); G. Xiao, T. R. Corle, and G. S. Kino, " Real-Time Confocal Scanning Optical Microscope, " Appl. Phys. Lett. 53, 716-718 (1988). By optical processing, the TSOM is basically a single-point confocal microscope with means for effectively scanning a point of a two-dimensional cross-section at a time. Examples of two techniques for reducing the amount of scans required to obtain a two-dimensional image in confocal alignment are described in [H. J. Tiziani H. -M. Uhde, "Three-Dimensional Analysis by a Microlens-Array Confocal Arrangement," Appl. Opt. 33 (4), 567-572 (1994); P. J. Kerstens, J. R. Mandeville F. Y. Wu, "Tandem Linear Scanning Confocal Imaging System with Focal Volumes at Different Heights," (U.S.Pat.No.5,248,876 issued Sept. 1993). The microlens-array confocal arrangement of Tiziani and Uhde ibid distinguishes out-of-focus images, such as using multi-pinhole sources and multi-element detectors in a confocal configuration. These systems can test many focal points at the same time, but they do not distinguish between out-of-focus images. As the densities of microlenses increase, the ability to differentiate out-of-focus images of the system becomes less good, resulting in increased complexity and cost of computer deconvolution required to produce a three-dimensional image. Moreover, the systems of Tiziani and Uhde ibid. Have significant limitations on the axis range. This range exceeds the focal length of the microlens, which is proportional to the diameter of the microlens for a given numerical aperture. Thus, as the densities of the microlenses increase, the allowable range of axes associated therewith is reduced.

Kerstens et al., Ibid systems combine many pinholes and matching pinpoint detectors to allow a large number of points at the same time in a confocal array. However, as described above, this advantage increases the cost and complexity of compromising the discrimination for out-of-focus images and resulting sequential computer deconvolution. The higher the pinhole densities are, the worse the system will fail to distinguish out-of-focus images. The highest discrimination can be achieved when using only one pinhole.

The application of confocal microscopes to the investigation of electronics is described in the paper [T. Zapf R. W. Wijnaendts-van-Resandt, "Confocal Laser Microscope For Submicron Structure Measurement," Microelectronic Engineering 5, 573-580 (1986); T. Lindow, S. D. Bennett, I. R. Smith, "Scanned Laser Imaging for Integrated Circuit Metrology," SPIE, 565, 81-87 (1985). The shaft discrimination provided by the confocal system makes the confocal system useful in a semiconductor manufacturing environment. For example, such a confocal system can provide improved investigation of height-dependent properties such as delamination of coatings and structures, blisters, and thickness. However, there are several problems associated with using confocal imaging systems for the investigation of electronics. For example, a single pinhole system requires too much time to scan an object in two directions. Optical systems for scanning laser beams on objects are too complex, and the spinning disk approach used in the TSOM results in alignment and maintenance problems.

The number of slices at different depths required (and consequently the amount of image data collected) depends on the number of heights to be measured and also on the resolution and performance of the desired height of the optical system. For a typical electronics survey, images of slices of different depths from 10 to 100 may be required. Moreover, data in multiple color bands may be required to differentiate the material. In confocal imaging systems, independent two-dimensional scans may be required for each desired elevation. If data for multiple color bands is required, multiple 2D scans are required at each elevation. By shifting the focus level, similar data can be obtained from adjacent planes, and a three-dimensional intensity data set may be required.

Thus, none of the conventional confocal microscopes can be configured for fast and / or reliable three-dimensional tomographic imaging, especially in the field of irradiation and imaging.

In contrast, for example, in confocal fluorescence studies where the concentration of the colored composition is high, the conventional microscopy approach still has several practical advantages, although the focus approach is more accurate and better. Most important of these advantages is that conventional microscopic approaches can use dyes excited in the ultraviolet range, and these dyes are much stronger and more efficient than dyes excited in the visible range. Although an ultraviolet (UV) laser is the source of the confocal microscope [M. Montag, J. Kululies, R. Jorgens, H. Gundlach, MF Trendelenburg, and H. Spring, "Working with the Confocal Scanning UV-Laser Microscope: Specific DNA Localization at High Sensitivity and Multiple-Parameter Fluorescence, Oxford) 163 (pt.2), 201-210, 1991; K. Kuba, S, -Y. Hua, and M. Nohmi, " Spatial and Dynamic Changes in IntracellularCa ²⁺ Optical Modifications Enabling Simultaneous Confocal Imaging With Dyes Excited by Ultraviolet-Light Spectroscopy "in Neurosci. Res. 10, 245-259, 1991. C. Bliton, J. Lechleiter and DE Clapham," Measured by Confocal Laser-Scanning Microscopy in Bullfrog Sympathetic Ganglion Cells, and Visible-Wavelength Light, "J. Microsc. 169 (pt. 1), 15-26, 1993] or UV dyes, or an ultraviolet laser can be coupled to the infrared dye using a two- (IR) light, but these techniques are costly and pragmatic.

Furthermore, cold charge coupled device (CCD) detectors used in conventional microscopy systems collect data in parallel, rather than serially, like a phototypical pliant (PMT) in confocal microscopy systems. As a result, if the cold-charge coupling device (CCD) can be manufactured to be capable of reading faster without degrading performance, the three-dimensional data recording rate of conventional microscopy systems can be improved, It can be shown that the computer deconvolution con- servation means with additional delay before it appears as a three-dimensional image takes time but is significantly higher than the recording rate of the confocal microscopy system.

The signal-to-noise ratio associated with statistical accuracy should also be considered when selecting a CCD detector and a slit or pinhole confocal microscope used to record a two-dimensional data array in parallel. The well capacity of a two-dimensional CCD pixel is 200,000 electron orders. This limits the statistical accuracy that can be achieved in a single exposure, as compared to what can be achieved using other photoemissive detectors such as devices of the PMT or photovoltaic devices. As a result, when applied to applications where the out-of-focus background is significantly larger than the focused image signal, considering the signal-to-noise ratio, if the other conditions are the same, Dimensional parallel recording has better performance than two-dimensional recording of data in a standard microscope configuration, and point-to-point recording of data in a single pinhole confocal microscope is more efficient than one-dimensional parallel recording of data in a slit confocal microscope It is a good conclusion.

Consideration of the statistical accuracy, such as signal-to-noise ratio, is important for the problem of system selection, when the slit confocal microscope rather than the standard microscope is affected as a single pinhole confocal microscope rather than the slit confocal microscope The residual signal from the out-of-focus image is larger or larger than the focused signal. For example, when the scattering of light radiation is dominant over absorption, it is time to investigate the biological sample deeply. In this case, a considerably longer computer deconvolution is required than the time required to obtain the data. Note that this is generally true for a single pinhole confocal microscope, like a slit confocal microscope, when looking for an in-focus image signal that is much smaller than the out-of-focus residual signal.

Although it is easier to digitize the signal from the CCD detector than the signal from the PMT (JB Pawley, Fundamental and Practical Limits Confocal Light Microscopy, " Scanning 13, 184-198,1991), the PMT is a single Device. On the other hand, CCDs have substantially more arrays of discrete detectors, and there is more noise associated with collecting pixel-pixel variations at offsets and sensitivities that characterize the operation [Y. Hiraoka, et al., Ibid Jerewicz, B. Wiese, J. Bryan, and LC Smith, " Quantum Fluorescence Microscopy Using Photomultiplier Tubes and Imaging Detectors, " Methods Cell Biol. 29, 239-267, Validation of an Imaging System: Steps to Evaluate and Validate a Microscope Imaging System for Quantitative Studies, " Methods Cell Biol. 30, 47-83, 1989]

This difference between the photo detectors used in the two methods of three-dimensional microscopy is not perfect. Because CCD detectors are optimal photo detectors for confocal microscopes that perform scanning functions by using holes in spinning disks (Petran, et al., Ibid., Xiao, et al., Ibid.)

Another technique known as " optical coherence-domain reflectometry " is used to obtain information about the three-dimensional characteristics of the system. This method is described in the following paper. : (1) "Optical Coherence-Domain Reflectometry: A New Optical Evaluation Technique," by R. C. Youngguist, S. Carr, and D. E. N. Davies, Opt. Lett. 12 (3), 158-160 (1987); (2) " New Measurement System for Fault Location In Optical Waveguide Devices Based on an Interferometric Technique, " K. Takada, I. Yokohama, K. Chida, and J. Noda, Appl. Opt. 26 (9), pp. 1603-1606 (1987); (3) " Guided-Wave Reflectometry with Micrometer Resolution, " B. L. Danielson and C. D. Whittenberg, Appl. Opt. 26 (14), 2836-2842 (1987). The OCDR method uses a coherent optical time domain reflectometry (OTDR) technique in that it uses broadband continuous-wave sources with a short coherence length instead of a pulsed light source Is different. The source beam enters an interferometer that includes a mirror that can move one arm inside and another arm that contains the optical system being tested, along with the reflected light reflected from the mirror providing the reference beam. Interference signals in the light reflected from the two coherently mixed arms are typically detected by the heterodyne method to produce the desired information in the optical system.

Heterodyne detection of backscattered signals in the OCDR technique is accomplished by the method of " white-light interferometry " where the beam is split into two arms of the interferometer, Reflected, and coherently recombined. This method utilizes the fact that interference fringes appear in the recombined beam only when the difference in optical path length between the two arms is less than the coherence length of the beam. The OCDR system described in the above-mentioned reference works (1) and (3) is based on this principle. Reference document (3) shows a fiber gabs obtained by scanning an adjustable mirror in a test system and measuring the intensity of the recombined light. Interference interferograms. Reference 1 also describes an improved method in which the mirror of the reference arm oscillates at a controlled frequency and magnitude and causes a Doppler shift in the reference signal which detects the bit frequency signal Is supplied to the filtering circuit.

Another variation of this technique is shown in reference (2), where the reference arm mirror is in a fixed position and the difference in length of the optical path exceeds the length of the coherence of the two arms. The combined signal is provided as a second Michelson interferometer with two mirrors, one fixed and the other movable. The movable mirror is scanned and the difference in optical path between the arms of the second interferometer compensates for the delay between the backscattered signal and the reference signal at a distant location of the mirror that can move relative to the scattered area . In practice, a phase change oscillating at a limited frequency is imposed on the signal from the backscattering region by means of a piezoelectric transducer modulator, in the fiber leading to the backscattering region. The output signal from the second Michelson interferometer is fed into a lock-in amplifier, which detects the bit frequency signal generated between the piezoelectric transducer modulation and the Doppler shift due to the motion of the scanning mirror. This technique has been used to measure irregularities in a glass optical waveguide with a short resolution of about 15 占 퐉. ["Characterization of Silica-Based Waveguides with a Interferometric Optical Time-Domain Reflectometry System Using a 1.3-㎛ Wavelength Superluminescent Diode , &Quot; K. Takada, N. Takato, J. Noda, and Y. Noguchi, Opt. Lett. 14 (13), 706-708 (1989)].

Another variation of the OCDR is a dual-beam partial coherence interferometer (PCI). This PCI has been used to measure the thickness of the fundus layers of the eye. [Measurement of the Fundus Layers by Partial Coherence Tomography, by W. Drexler, CK Hitzenberger, H. Sattmann, and AF Fercher, In the PCI used by Drexler, et al., External Michelson interferometers have a high spatial coherence and a high spatial coherence of 15 [mu] m Split the light of a very short coherence length into two parts, the reference beam 1 and the measuring beam 2. At the interferometer exit, the two components recombine to form a coaxial dual beam The two beam components have a path difference of twice the interferometer arm length difference, illuminate the eye and are reflected at the interface of several intraocular, which distinguishes media with different refractive indices Thus, each beam component 1 and 2 is coupled to the < RTI ID = 0.0 > If the optical distance of the two boundaries in the eye is equal to twice the interferometer arm length difference, then the total length of the same path in the entire volume is < RTI ID = 0.0 > There are two subcomponents that actually cause interference by moving the interferometer arm length difference between the interferometer arm length and the interferometer arm length difference, where each interferometer arm length difference is equal to the Intro color light length where the interference pattern is observed. The absolute position of the interface is determined in vivo with an accuracy of 5 [mu] m. However, the PCI suffers from dimming caused by movement of the object for the time required to perform 3-D scanning.

[E. A. Swanson, J. A. Izatt, M. T. Hee, D. Huang, C. P. Lin, J. S. Schuman, C. A. Puliafito, J. G. Fujimoto, "In Vivo Retinal Imaging by Optical Coherence Tomography," Opt. Lett. 18 (21), 1864-1866 (1993); E. A. Swanson, D. Huang, J. G. Fujimoto, C. A Puliafito, C. P. Lin, J. S. Schuman, " Method and Apparatus for Optical Imaging with Means for Controlling the Longitudinal Range of the Sample, Pat. No. 5,321,501 (1994. 6.14) report another variant of OCDR called optical coherent tomography (OCD) for retinal imaging in vivo.

The patent describes optical imaging of a sample, which is provided by longitudinal scanning or positioning in the sample, by changing the optical path length relative to the sample and the optical path to the reference reflector, or by changing the optical properties of the output from the light source applied to the device And describes the apparatus and method to be performed. Scanning of the transverse in one or two dimensions can be accomplished by providing controlled relative movement in this direction between the sample and the probe module and / or by adjusting the optical radiation in the probe module to a selected lateral position / RTI > The known spatial resolution is less than 20 μm with a sensitive sensitivity (100 dB dynamic range). However, OTC is a problem due to the motion of the object during the time required for 3D scanning.

Optical interference profiler is widely used for three-dimensional profiles of surfaces when non-contact methods are required. The problem is that the profiler typically uses phase-shifting interferometic (PSI) techniques and is fast, precise and repeatable, but the surface must be flat compared to the average wavelength of the light source. The discontinuity of a surface larger than a quarter wavelength (typically 150 nm) can only be degraded by single wavelength measurements due to the periodic nature of the interference. Multi-wavelength measurements can extend this range, but the constraints imposed on wavelength accuracy and ambient stability can be severe (see U.S. Patent No. 4,340,306, issued Feb. 20, 1982, entitled " Optical System for Surface Topography Measurements & number)

The scanning white-light interferometer (SWLI) based profiler overcomes many of the limitations of the traditional PSI profiler for measuring rough or discontinuous surfaces. Several papers describe this technique in detail (Refs.2-7 in L. Deck and P. de Groot, Appl. Opt. 33 (31), 7334-7338 (1994)). Typically, these professors have a contrast-based attribute (i.e., a peak contrast or a peak) for each point in the field of view while axially translating one arm of co- Record the position of the pit. A common problem with this technique is that it has to do a huge amount of computation to compute the contrast for each point in real time. Often contrast calculation alone is not accurate enough due to the discrete sampling interval, requiring an increase in sampling density, This makes the acquisition process slower. The coherence probe microscope (CPM) is an example of this kind of profiler. (M. Davidson, U.S. Patent No. 4,818,110 (Apr. 4, 1989), entitled " Apparatus and Method Using an Integrated Circuit and a Two-Beam Interfering Microscope for such Type Inspection "; M. Davidson, K. Kaufman, I M. Mazor, F. Cohen, " Application of Interference Microscopes to Integrated Circuit Inspection and Instrumentation " SPIE 775, 233-247 (1987); M. Davidson, K. Kaufman, I.Mazord, " coherence applied to integrated circuit instrumentation U.S. Patent No. 5,112,129 (May 5, 1992) entitled " Image Enhancement Method for Probe Microscope "). Typical profiler and special CPM can not handle 3D objects, have a typical background of traditional interference microscopy, are sensitive to vibration, and require intensive analysis of the computer.

Profiling based on triangulation also overcomes many of the limitations of the traditional PSI profiler, but has a problem of reduced height and lateral spatial resolution and has a large background outside the image. The application of this technique is described in a paper entitled "Parallel 3D Sensing by Color Coded Triangulation" by G. Hazzler and D. Liter (Appl. Opt., 32 (35), 7164-7165 (1993)). . This method, used by G. Hazler and D. Litter, is based on the following principle: The color spectrum of a white light source is imaged onto the object by illumination from one direction. The object is observed by a color TV camera from the viewing direction different from the lighting direction. The hue of each pixel is the measured distance from the reference plane. The distance can be calculated by the three (red-green-blue) output channels of a charge coupled device (CCD) camera and this calculation can be implemented in real time on the TV. However, resolution in height and side-space dimensions is much less than that obtained with PSI or SWLI, and there is a large background, and the trigonometric profiler has noise characteristics of non-interferometric measurement techniques. Trigonometric profiler is also limited to plane profiling.

One of the problems faced in the white light interferometer (WLI) is phase ambiguity. The profile measurement method that has been interested in the phase ambiguity problem is Opt. Lett. 19 (13), 995-997 (1994), which is the Distributed Interference Profile System (DIP) proposed by J. Schmidter and L. Joe. A similar approach to WLI is also described in the paper entitled " Absolute Distance Measurement with Synchronously White-Light Channelized Spectral Interferometry ", Pure Appl. Opt. 4, 643-651 (1995), U. Snell, E. Jimerman, It was reported by Dendleraker.

In general, the phase ambiguity problem can be completely eliminated by the use of DIP. In a DIP device, the parallel beam of a white light source strikes the front face of the apochromatic microscope objective perpendicular to the actual wedge of the interferometer. The subject interferometer is formed by the object surface and the inner surface of the reference plate. The light is then reflected back to the grating spectral slit, which disperses the underwater side-effect device invisible fringe pattern and projects the spectrum onto a linear array detector. Each point on the surface selected by the spectrographic slit at the detector provides a dispersed spectrum of air gaps in the subject's interferometer. The fringe pattern can be calculated by a filtering method that obtains phase information from the Fourier transform and the intensity variance of the wedge-type interferogram.

Although phase ambiguity problems can be eliminated with the use of DIP, DIP is not suitable for applications requiring investigation of 3D objects. This is the result of a relatively large background inherent in the DIP from out-of-focus images. The background problem is compared with the background problem encountered when trying to generate a three-dimensional image using standard interference microscopy.

A method and apparatus for spectrally resolving measurements of reflected, emitted, and scattered light from a specimen is disclosed in A. E. Dickson, S. Damaskino, and J.W. U.S. Patent No. 5,192,980 (1993.3.9) entitled " Method and Apparatus for Spatially and Spectrally Degraded Measurements " by Bowron. In an embodiment of the method and apparatus of Dixon et al., The character of the specimen is that the apparatus and method are configured in a non-interference, non-confocal fashion with a dispersive element preceding the detector in terms of the intensity of the reflected, emitted, and scattered light to be. Dixon et al. Have a large background from an out-of-focus image inherent in a standard microscope and are of the non-confocal type.

Dixon et al. Also include non-interfering confocal devices that allow measurements to be made in a reduced background. However, the limitation on intensity measurements for confocal devices as well as non-confocal devices has significant limitations on information about specimens obtained from reflected or scattered light as a result of using non-interference techniques. The intensity measurement yields the size information of the square of the amplitude of the reflected or scattered light from the specimen as a result of loss of information about the phase of the amplitude of the reflected or scattered light. Dixon et al. Further include an embodiment incorporating a Fourier transform spectral system in an unfocused imaging system. A Fourier transform spectral-based device such as Dickson has the disadvantage of having a large background from an out-of-focus image that is inherent in an unfocused image system.

An apparatus for simultaneously performing multiple wavelength measurements with a non-interfering, confocal imaging system is disclosed in US Patent No. 5,537,247 (July 1996), which is named " Single Upper Confocal Imaging System " The apparatus of the present invention comprises a confocal scanning imaging system using only one aperture for light incident from a light source and light returning from the object, a series of beam splitters and a beam splitter for selectively directing reflected light of a different wavelength to a series of detectors And an optical wavelength filter. The device of the EXCO has the advantage of enabling simultaneous measurement for different wavelengths and has the advantage of a background reduction confocal imaging system from an out-of-focus image. However, the limitation on intensity measurement is a consequence of using the non-interferometry technique, and there is a significant limitation on the information about the specimen obtained from reflected or scattered light. The intensity measurement yields the size information of the square of the amplitude of the reflected or scattered light from the specimen as a result of loss of information about the phase of the amplitude of the reflected or scattered light.

G.Q. Axio, T.R. Collier, G.S. A paper entitled " Real-time Confocal Scanning Optical Microscope " by Keno, Appl. Phys. In Lett., 53 (8), 716-718 (1988), when using white light in a confocal microscope, the chromatic aberration of the objective lens is within the focal point of the image at different heights in the specimen, but all appear in different colors. Axio et al. Have demonstrated this by producing images of semiconductor integrated circuits at four different wavelengths. H.J. A paper entitled " Three-Dimensional Imaging Sensing by Color Confocal Microscopy " Optics, 33 (10), 1838-1843 (1994), disclose a method for obtaining height information without physically scanning an object, such as a white light in which chromatic aberration is precisely inserted into a microscope objective lens, a non- . The camera in black and white film sequentially combines the intensity and tone of the color of each target point with three selected color filters. Although a confocal microscope is used simultaneously in the examples disclosed by Axio et al., Tijjian and Ude and has a reduced background from the out-of-focus image, they are limited to intensity measurements. The limitation on intensity measurement is a direct consequence of using non-interferometry techniques, and there is a significant limitation to the information on specimens that can be obtained from reflected or scattered light, as described in connection with Dixon et al.

The interference microscope is G.S. Keno and S.C. A paper entitled " Miura Correlation Microscope " Opt., 26 (26), 3775-3783 (1990), a paper entitled " Three Dimensional Imaging in Interfering Microscopes " Opt., 31 (14), 2550-2553 (1990). The device of the keno and needle employs an interferometric, non-confocal microscope with spatially and temporally incoherent light sources, each using a correlation signal between the object and the reflected beam from the mirror as the detected output. It is possible to measure the amplitude and the phase of the reflected beam from the object with the device of the keno and needle. However, the interferometric device of Keno and Needle has the disadvantage of serious background problems and the level of background from a typical, out-of-focus image found in standard interferometry, non-confocal microscopy systems.

An interferometric device is disclosed in U. S. Patent No. 5,565, 966 (Oct. 15, 1996) to A. Kunittel, which obtains a spectral image of an object and simultaneously displays a clock in the spatial resolution and depth direction of the lateral direction, Quot; stationary optical spectrum imaging < / RTI > in opaque objects by special optical focusing with optical signal detection and optical signal detection ". The device disclosed by Kunittel has an unfocused imaging system and typically features a dispersive optical element in the interior of the interferometer and color objective lens. The dispersive element makes it possible to record information about the scattered light amplitudes at different light wavelengths and the use of an interferometer makes it possible to record information about the phase and magnitude of the amplitude of the reflected or scattered light, The use of a lens makes it possible to record information about the clock in the depth direction. However, Kunittel's interferometric device has the disadvantage of a serious background problem and the level of background from a typical, out-of-focus image found in standard interferometric, non-autofocus microscopy systems.

One of the main purposes of the Kunittel's instrument is to simultaneously image two areas of the object separated from the depth dimension by the use of a chromatic objective of two different orders constructed on the part of the zone plate I was doing. As a result, the signal recorded by the detector of the apparatus consists of an image superimposed from two separate depth positions at the object. Thus, in addition to the presence of a high background from the out-of-focus image, as previously described, a complex transformation calculation must be performed by the computer to extract the image for a given depth from the doubly printed infocus image There is a serious problem with the transformation calculations required for a double-printed image obtained in the mentioned example of the network: the result of the transformation calculation is relatively accurate near the target surface, but as the depth in the sample increases, . This problem generally does not occur in the conversion circuit if there is only one point in focus in the detector.

The background problem that arises in the interference microscope is reduced in the confocal microscope of the interference type, see D. K. Hamilton and C.J.R. Optica Acta, 29 (12), 1573-1577 (1982), entitled " Confocal Interference Microscope " The system is based on a confocal microscope in which the object is scanned in proportion to the focused laser position, which is arranged to match the rear projected image of the point detector. The interferometric form of the reflective confocal microscope is based on a Michelson interferometer in which one beam is focused on the object. The system can be used to detect an important feature of the reduced background from the intrinsic out-of-focus image in the confocal microscopy system . However, Hamilton and Shepherd's confocal interference microscopes measure the reflected signal only at one point at a point on a three-dimensional object. Scanning of an object at a point at any point also makes the system sensitive to sample motion that is not associated with a scan during the required data acquisition.

A key component that is important to the efficient use of high-performance computers is memory. Because of the huge data storage requirements of these devices, small, low cost, high capacity, high speed memory devices are required to handle the amount of data that can perform parallel calculations. Such a data storage request can be provided by a three-dimensional memory.

In a two-dimensional memory, the maximum theoretical storage density (proportional to 1 /? ² ) is 3.5 * 10 ⁸ bits / cm ³ order for? = 532 nm and the maximum storage density is 6.5 * 10 ¹² bits / a cm ^3. The maximum value represents the upper limit of storage capacity when using a single bit binary format at each memory site. This upper limit value can be increased by using a recording medium on which amplitude or amplitude and phase information of different levels are recorded. Holographic recording in a phase-recording medium is an example of the latter mode.

In other recording modes, the mode of single bit binary format, amplitude in base N format or amplitude and phase in (base N) * (base M) format, voxel ) And thus the storage density is limited by the single-noise ratio that can be obtained, and the single-noise ratio is generally inversely proportional to the volume of the voxel. In particular, for amplitude or amplitude and phase recording modes, the number of independent information that can be stored in the voxel is also limited by the single-noise ratio that can be obtained.

What is needed is an out-of-focus image that is less than that inherent in conventional confocal and confocal interference microscopes. The out-of-focus image has a sensitivity to image data, Reduced sensitivity, the need for reduced computational degradation associated with reduced sensitivity to out-of-focus images, potential for high signal-to-noise ratios inherent in confocal interference microscopy systems, And a potential for measuring the complex amplitude of the scattered and / or reflected light beam.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide an apparatus and method for reading information from an area at different depths in an optical disc.

It is an object of the present invention to provide an apparatus and a method for reading information from an area at multiple depths in an optical disc.

It is an object of the present invention to provide an apparatus and a method for simultaneously reading information from an area at multiple depths in an optical disc.

It is an object of the present invention to provide an apparatus and a method for reading information from an area in or on an optical disc.

It is an object of the present invention to provide an apparatus and a method for simultaneously reading information from an area on or in an optical disc.

It is an object of the present invention to provide an apparatus and a method for simultaneously reading information from an area in multiple tracks and multiple tracks in or on an optical disc.

It is an object of the present invention to provide an apparatus and method for simultaneously reading information from multiple tracks and regions at multiple depths in an optical disc.

It is an object of the present invention to provide an apparatus and a method for recording information in an area at multiple depths in an optical disc.

It is an object of the present invention to provide an apparatus and a method for simultaneously recording information in an area at multiple depths in an optical disc.

It is an object of the present invention to provide an apparatus and method for recording information in an area on or in an optical disc in multiple tracks.

It is an object of the present invention to provide an apparatus and a method for simultaneously recording information in an area in multiple tracks in or on an optical disc.

It is an object of the present invention to provide an apparatus and a method for simultaneously recording information in multiple tracks and regions in multiple depths in an optical disc.

It is an object of the present invention to provide an apparatus and a method for recording information in an area at multiple depths in an optical disc having a high density.

It is an object of the present invention to provide an apparatus and a method for simultaneously recording information in an area at multiple depths in an optical disc having a high density.

It is an object of the present invention to provide a method and apparatus for recording information at high density at the position of multiple tracks on or in an optical disc.

It is an object of the present invention to provide a method and apparatus for simultaneously recording information at high density in the position of multiple tracks on or in an optical disc.

It is an object of the present invention to provide a method and apparatus for simultaneously recording information at high density at multiple depths and positions of multiple tracks in an optical disc.

It is an object of the present invention to provide fast and stable one-, two-, and three-dimensional tomographic complex amplitude imaging.

It is an object of the present invention to provide an improved tomographic complex amplitude imaging technique without the disadvantages of the prior art.

It is yet another object of the present invention to provide a Tomo graphics complex amplitude imaging technique that conveniently reduces or eliminates statistical error effects of light from out-of-focus image points.

It is yet another object of the present invention to provide an improved tomography complex complex amplitude imaging wherein the systematic error effect of the out-of-focus optical image is greatly reduced or eliminated.

It is yet another object of the present invention to provide a tomographic amplification imaging technique capable of substantially simultaneous imaging of an object at multiple imaging points.

It is a further object of the present invention to provide a convenient technique for tomographic amplification imaging in 1, 2, and 3 dimensions, together with means for obtaining a signal-to-noise ratio for an image achievable with an interferometry system.

It is a further object of the present invention to provide a Tomo graphics complex amplitude imaging system and technique that avoids the difficulty of calculating when solving nonlinear differential equations.

It is a further object of the present invention to provide a convenient technique for tomographic amplification of the amplitude of a line section or a two-dimensional section of the object, despite the movement of the object.

These embodiments and variations to be described below are divided into five groups of embodiments. Some embodiments of the first group of embodiments and variations thereof produce a one-dimensional image that is substantially orthogonal to the one-dimensional image generated by the embodiments of the second group of embodiments and corresponding variations thereof, The information in the image is obtained simultaneously with background reduction and compensation. Still other embodiments of the first group of embodiments generate a two-dimensional image that is substantially orthogonal to the two-dimensional image generated by the embodiments of the second group of embodiments and corresponding ones of the variations, Is obtained simultaneously with background reduction and compensation.

Some embodiments of the third group of embodiments and variations thereof produce a one-dimensional image that is substantially orthogonal to the one-dimensional image generated by the embodiments of the fourth group of embodiments and corresponding variations thereof, The information in the image is obtained simultaneously without background reduction and compensation. Some embodiments of the third group of embodiments and variations thereof generate a two-dimensional image that is substantially orthogonal to the two-dimensional image generated by the embodiments of the fourth group of embodiments and corresponding variations thereof, The information in the image is obtained simultaneously without background reduction and compensation.

Embodiments of the fifth group of embodiments and variations thereof generate a multidimensional image as a series of single point images, and a single point image is obtained with background reduction and compensation.

As described briefly, by focusing the optical emission from a broadband spatially coherent point source to a source pinhole, the complex amplitude of the in-focus image and the intensity of the out-of-focus image Methods and apparatus for discriminating complex amplitudes are provided from a first group of embodiments. The light rays emerging from the source pin hole become parallel to the first phase shifter. The phase of the first portion of the parallelized rays is shifted by the phase shifter to produce a first amount of phase shifted rays and the phase of the second portion of the parallelized rays is shifted by the phase shifter to produce a second amount of phase shifted Makes rays. The first and second amounts of phase-shifted light rays are focused on the first spot.

The first positive phase-shifted beam emerging from the first spot is parallel and directed to a beam splitter. A first portion of the collimated beam passes through a beam splitter to form a first positive beam of probe and a second portion of the collimated beam is reflected by the beam splitter to form a first positive reference beam. The second amount of phase-shifted light rays emerging from the first spot become parallel and directed towards the beam splitter. A first portion of the collimated beam passes through a beam splitter to form a second amount of probe beam and a second portion of the collimated beam is reflected by the beam splitter to form a second positive reference beam.

The first and second amounts of light of the probe beam are directed to the second phase shifter. The first positive ray of the probe beam is phase shifted to form a third positive quantity of the probe beam and the second quantity of the beam of the probe beam is phase shifted to form a fourth positive quantity of the probe beam, The net phase shifts produced by the first and second phase shifters are the same for the probe beam of FIG. The third and fourth amounts of the probe beam are focused by the first probe lens to form a line image on the object material, thereby illuminating the material of interest. The line image is aligned close to the optical axis of the first probe lens and the length of the line image along the optical axis is determined by the combination of factors such as the optical bandwidth of the source and the chromatic aberration and focus depth of the adjustable first probe lens .

The beams of the first and second amounts of reference beams are directed to the third phase shifter. The beams of the first amount of reference beam are phase shifted to form a third amount of reference beam and the beams of the second amount of reference beam are phase shifted to form a fourth amount of reference beam, The net phase shifts produced by the first and third phase shifters are the same for the reference beam of FIG. The third and fourth amounts of the reference beam are focused on the spot on the reference mirror by the reference lens. The reflected and / or scattered light beams of the third and fourth positive probe beams emerging from the illuminated object in the direction of the probe lens form a scattered probe beam and are collimated and sent to the second phase shifter by the probe lens. The phase of the first portion of the parallelized rays is mutated to produce a first scattered probe beam amount of the phase shifted rays and the phase of the second portion of the parallelized rays is mutated to produce a second scattered Make the amount of probe beam. The beams of the first and second ablated probe beam quantities are directed to a beam splitter. The portions of the first and second scattered probe beam amounts are reflected by the beam splitter to form third and fourth amounts of scattered probe beams, respectively. The parallel rays of light in the third and forth of the scattered probe beam are focused on the spatial filter pinhole by a spatial filter lens.

The reflected light rays emerging from the spot on the reference mirror in the direction of the reference lens form a reflected reference beam and become parallel and transmitted to the third phase shifter by the reference lens. The phase of the first portion of the parallelized rays is mutated to produce a first reflected reference beam amount of the phase shifted rays and the phase of the second portion of the parallelized rays is mutated to form a second reflected Make a reference beam amount. The first and second reflected reference beam amounts of light are directed to a beam splitter. The portions of the first and second reflected beam amounts are transmitted by a beam splitter to form third and fourth amounts of reflected reference beams, respectively. The parallel rays of the third and fourth amounts of reflected reference beam are focused onto the spatial filter pinhole by a spatial filter lens.

The third and fourth portions of the scattered probe beam pass through a spatial filter pinhole to form spatially filtered third and fourth amounts of scattered probe beams, respectively. The spatially filtered third and fourth amounts of scattered probe beam are collimated and transmitted by a dispersive element lens to a dispersive element, preferably a reflecting diffraction grating.

The third and fourth portions of the reflected reference beam pass through the spatial filter pinholes to form spatially filtered third and fourth amounts of reflected reference beams, respectively. The spatially filtered third and fourth reflected reference beams become parallel and are directed to the dispersive element by a dispersive element lens.

Each portion of the spatially filtered third and fourth amounts of scattered probe beam from the dispersive element is passed through a detector lens and filtered into a wavenumber and spatially filtered third and fourth amounts of scattered probe beams . The wavenumber filtered and spatially filtered third and fourth amounts of scattered probe beam are focused by a detector lens to form a line image on a plane comprising a linear array of detector pinholes. Each portion of the spatially filtered third and fourth reflected reference beams emerging from the dispersive element passes through a detector lens and is filtered by a wavenumber and the spatially filtered third and fourth reflected reference beams . The wavenumber filtered and spatially filtered third and fourth reflected reference beams are focused by a detector lens and are filtered by wave number on planes comprising a linear array of pin holes and spatially filtered third and fourth 4 < / RTI > positive reference beam.

A third and fourth amount of scattered probe beam transmitted from the detector pin hole, double-printed, wavenely filtered and spatially filtered, and a third and fourth amount of spatially filtered reflected reference beam The intensity of the parts is measured by a multi-pixel detector consisting of a linear array of pixels as a first array of measured intensity values. The phases of the third and fourth amounts of reflected reference beams filtered by the wavenumber filtered and spatially filtered are shifted by radians by a fourth phase shifter to produce a first phase shifted and wavenumber filtered spatially filtered third and fourth Thereby forming a positive reflected reference beam. A third and fourth amount of scattered probe beam transmitted from the detector pin hole, double-printed, wavenely filtered and spatially filtered, and a third, fourth, and first shifted, wavenely filtered spatially filtered, The intensity of the portions of the reference beam is measured by a multi-pixel detector as a second array of measured intensity values.

The phases of the third and fourth amounts of reflected reference beams filtered by the wavenumber filtered and spatially filtered are shifted by the additional radians by a fourth phase shifter to produce a second phase shifted and wavenumber filtered spatially filtered third and 4 positive reflected reference beams, respectively. A third and fourth amount of spatially filtered scattered probe beam filtered with a double-printed wavenumber transmitted from a detector pin hole, and a third and fourth amount of reflected, second phase shifted, wavenely filtered spatially filtered spatially filtered The intensity of the portion of the reference beam that is measured is measured by the multi-pixel detector as a third array of measured intensity values.

The phases of the third and fourth reflected reference beams filtered and spatially filtered are shifted by an additional radian by a fourth phase shifter to produce a third phase shifted and wavenhed filtered spatially filtered third and 4 positive reflected reference beams, respectively. A third and fourth amount of scattered probe beam transmitted from the detector pinhole, double-printed, wavenely filtered and spatially filtered, and a third phase shifted, wavenumber filtered and spatially filtered third and fourth The intensity of the portion of the reflected reference beam is measured by a multi-pixel detector as a fourth array of measured intensity values.

In the next step, the first, second, third, and fourth arrays of measured intensity values are sent to the computer for processing. The elements of the second array of measured intensity values are subtracted by the computer from the corresponding elements of the first array of measured intensity values and are focused at the plane of the detector pinhole with the effect of the nearly canceled out- A measurement of the first array of component values of the complex amplitude of the naturally scattered probe beam is calculated. The elements of the fourth array of measured intensity values are subtracted by the computer from the corresponding elements of the third array of measured intensity values and are focused at the plane of the detector pinhole with the effect of the nearly canceled out- A measurement of the second array of component values of the complex amplitude of the naturally scattered probe beam is calculated.

The first and second arrays of component values of the scattered probe beam amplitudes are the values of the quadrature components and are the complex of the in-focus scattered probe beam in the plane of the detector pinhole with the effect of the nearly canceled out- Gives an accurate measurement of the amplitude within a complex constant. Using computer and computer algorithms known to those skilled in the art, an accurate one-dimensional representation of the line section of the material of interest is obtained without the scanning of the required material of interest. The direction of the line section is the optical axis direction of the probe lens. The line section may be cut through one or more surfaces of the target material, or may be placed on the surface of the target material. Using computer and computer algorithms known to those of ordinary skill in the art, accurate two-dimensional, three-dimensional representations of the material of interest can be obtained by first, second, and third measurements of the measured intensity values obtained through scanning of the material of interest, , And a two-dimensional and three-dimensional array of a fourth array, respectively. A preferred line section, surface section, or volume section of the material of interest may pass or contain one or more surfaces of the material of interest. Scanning of the material of interest is accomplished by a material that is systematically moved as a computer-controlled translator. Computer algorithms may include computer deconvolution, and version techniques, which are known to those skilled in the art and are integral equations, can be applied to an out-of-focus image in which the first component of the component value of the amplitude of the probe beam scattered by the apparatus of the present invention And compensation beyond the compensation obtained in the second array.

By focusing on the optical emission from a broadband, spatially extended and spatially incoherent line source to a linear array of source pinholes including the electronic processing means and apparatus of the above-described embodiment, according to the second embodiment , A method and apparatus for distinguishing the complex amplitude of an in-focus image and the complex amplitude of an out-of-focus image, wherein the source pinhole of the first embodiment is replaced by a linear array of source pinholes, The spatial filter pinholes are replaced by a linear array of spatial filter pinholes and the linear array and multi-pixel detector of the detector pinhole of the first embodiment are replaced by a multi-pixel detector consisting of a two-dimensional array of detector pinholes and a two- . The linear array of source pin holes and the linear array of spatial filter pin holes are perpendicular to the plane defined by the dispersive element. A two-dimensional array of detector pixels and detector pinholes is aligned with an image of a linear array of source pinholes in the in-focus plane in the multi-pixel detector.

The elements of the measured array of the first and second component values of the wavenumber-filtered and spatially filtered scattered probe beam amplitudes are the values of the quadrature components, with the effect of light from the nearly canceled out-of-focus image Gives an accurate measurement of the complex amplitude of the in-focus scattered probe beam in the plane of the two-dimensional linear array of detector pin holes within a complex constant. Using computer algorithms known to those skilled in the art, a precise two-dimensional representation of a two-dimensional section of the material of interest is obtained without the need for scanning. The two-dimensional section is selected by the respective directions of the optical axis of the probe lens and the linear array of the source pin holes. The two-dimensional section may be cut through one or more surfaces of the target material, or may be placed on the surface of the target material. Using computer algorithms known to those skilled in the art, an accurate three-dimensional representation of an object is obtained from a three-dimensional array of first, second, third, and fourth intensity values obtained through scanning of objects in substantially one dimension Loses. A three-dimensional representation of the material of interest may include a representation of one or more surfaces of the material of interest. Computer algorithms may include computer deconvolution, and version techniques, which are known to those skilled in the art and are integral equations, can be applied to an out-of-focus image in which the first component of the component value of the amplitude of the probe beam scattered by the apparatus of the present invention And compensation beyond the compensation obtained in the second array.

According to a modification of the second embodiment, the optical radiation from the broadband, spatially extended and spatially incoherent line source to the source slit including the electronic processing means and apparatus of the second embodiment described above is focused Focus image and an out-of-focus image, wherein the linear array of source pin holes of the second embodiment is replaced by a source slit, and the linear filter of the linear filter of the spatial filter pin hole of the second embodiment The array is replaced by a spatial filter slit, and the directions of the source slit and the spatial filter slit are perpendicular to the plane defined by the dispersive element.

The elements of the measured array of the first and second component values of the wavenumber-filtered and spatially filtered scattered probe beam amplitudes are the values of the quadrature components, with the effect of light from the nearly canceled out-of-focus image Gives an accurate measurement of the complex amplitude of the spatially filtered scattered probe beam filtered in the in-focus wave in the plane of the two-dimensional array of detector pin holes within a complex constant. Using computer algorithms known to those skilled in the art, a precise two-dimensional representation of a two-dimensional section of the material of interest is obtained without the need for scanning. The two-dimensional section is selected by the optical axis of the probe lens and the direction of the source slit, respectively. Using computer and computer algorithms known to those skilled in the art, an accurate three-dimensional representation of the material of interest is obtained from a three-dimensional array of first, second, third and fourth intensity values obtained through scanning of the material of interest in one dimension Loses. Scanning of the target material can be achieved by systematically moving the target material in one dimension as a computer controlled trans- lator. Computer algorithms can include computer deconvolution, and versioning, an integral equation known to those skilled in the art, requires correction for out-of-focus images beyond the compensation obtained by the inventive apparatus.

Alternative embodiments of the first and second preferred embodiments of the present invention may be implemented using substantially the same electronic processing means and additional optical means as those used in the primary devices of the first and second preferred embodiments of the present invention , And the ability to enhance and / or optimize the signal-to-noise ratio. The additional optical means comprise a modified path for the reference beam and the probe beam and are thus filtered in a wavenumatic focus spatially on the detector pinhole selected for either of the first or second embodiment The amplitudes of the filtered and reflected reference beams can be adjusted with respect to the amplitudes of the probe beams that are imaged and waved filtered and spatially filtered on the selected detector pinholes of either the first embodiment or the second embodiment .

According to a third embodiment of the present invention, there is provided an apparatus for adjusting, improving and / or optimizing a signal-to-noise ratio comprising the apparatus of the first embodiment described above, means for filtering, Focused images on the selected detector pinholes are filtered with respect to the amplitude of the scattered probe beam and filtered by spatially filtered and optical means for adjusting the amplitude of the reflected reference beam, A method and apparatus for distinguishing the complex amplitude of an orbital image are provided. The light from a broadband spatially incoherent point source is focused on the source pinhole. The light rays coming from the source pin hole become parallel and are sent to the first phase shifter. The phase of the first portion of the parallel rays is shifted to produce a first amount of phase shifted rays and the phase of the second portion of the parallel rays is shifted to produce a second amount of phase shifted rays.

The first and second amounts of phase shifted light rays impinge on the first beam splitter. A first portion of the first amount of phase shifted light beam passes through a first beam splitter to form a first amount of the probe beam and a second portion of the first amount of phase shifted light ray is reflected by the first beam splitter Thereby forming a first amount of reference beam. The first portion of the second amount of phase shifted light beam passes through the first beam splitter to form a second amount of the probe beam and the second portion of the second amount of phase shifted light ray is reflected by the first beam splitter Thereby forming a second amount of reference beam. The first and second amounts of the probe beam are focused on the first probe beam spot. The first and second amounts of the reference beam are focused on the first reference beam spot.

A first positive ray of the probe beam emitted from the first probe beam spot is collimated and directed to a second beam splitter. A portion of the parallel rays pass through the second beam splitter to form a third amount of the probe beam. A second amount of the beam of the probe beam that is emitted from the first probe beam spot is collimated and directed to the second beam splitter. A portion of the parallel rays pass through a second beam splitter to form a fourth quantity of the probe beam. The third and fourth amounts of light of the probe beam are directed to the second phase shifter. A third amount of light beam of the probe beam passes through the second phase shifter and is phase shifted to form a fifth amount of the probe beam. A fourth positive ray of the probe beam is phase-shifted to form a sixth quantity of the probe beam through the second phase shifter, and the first and second quantities of the probe beam, The net phase shift is caused by the phase shifter.

The first positive ray of reference beam emitted from the first reference beam spot is collimated and directed towards the third phase shifter to appear as a third amount of reference beam. The second quantity of light of the reference beam emitted from the first reference beam spot is collimated and directed to the third stage to appear as a fourth quantity of the reference beam and the third quantity and the fourth quantity of the reference beam are equal A net phase shift is generated by the first and third phase shifters. A portion of the third amount of the reference beam is reflected by the third beam splitter to form a fifth amount of the reference beam. A portion of the fourth amount of the reference beam is reflected by the third beam splitter to form a sixth amount of the reference beam. The collimated fifth and sixth amounts of the reference beam are focused on the second reference beam spot on the reference mirror by the reference lens.

The collimated fifth and sixth quantities of the probe beam are focused by the probe lens to form a line image on the target material to illuminate the target material. The line image is aligned close to the optical axis of the probe lens and the length of the line image along the optical axis is determined by a combination of factors such as the optical bandwidth of the source and the chromatic aberration and focus depth of the probe lens.

The reflected and / or scattered rays of the fifth and sixth amounts of the probe beam emitted from the object imaged in the direction of the probe lens form a scattered probe beam. The scattered probe beam is collimated by the probe lens and directed to the second phase shifter. The phase of the first portion of the collimated light beam is varied to produce a first scattered beam amount of the phase-shifted light beam, and the phase of the second portion of the collimated light beam is shifted to produce a second And is varied to generate the amount of scattered probe beam. The first and second scattered probe beam amounts of light are directed to a second beam splitter. A portion of the first and second scattered probe beam amounts are each reflected by a second beam splitter to form third and fourth amounts of the scattered probe beam. The collimated rays of the third and fourth amounts of the scattered probe beam are focused on the spatial filter pinhole by a spatial filter.

A reflected light beam that is emitted from the second reference beam spot and reflects to the reference mirror in the direction of the reference lens forms a reflected reference beam and is collimated and directed to the third beam splitter by the reference lens. A portion of the reflected reference beam is transmitted by the third beam splitter and impinges on the fourth beam splitter. The phase of the first portion of the transmitted beam is shifted to produce a second reflected reference beam amount of the phase-shifted beam and the phase of the second portion of the transmitted beam is shifted to produce a second reflected reference beam of phase- And is varied to generate a beam amount. The first and second reflected reference beam amounts of light are directed to a second beam splitter. A portion of the first and second reflected reference beam amounts are each transmitted by a second beam splitter to form a third amount of a third light beam of the reflected reference beam. The third light of the reflected reference beam and the parallel rays of the fourth light are focused on the spatial filter pinhole by a spatial filter.

Each portion of each of the third and fourth amounts of the scattered probe beam passes through a spatial filter pinhole to form a third and a fourth spatially filtered amount of scattered probe beam. The spatially filtered third and fourth quantities of the scattered probe beam are collimated and directed by a spectroscopic element lens to a spectroscopic element, preferably a reflection diffraction grating.

A portion of each of the third and fourth amounts of the reflected reference beam passes through the spatial filter pinhole to form a third and a fourth spatially filtered amount of the reflected reference beam, respectively. The spatially filtered third and fourth quantities of the reflected reference beam are collimated and directed to the spectroscopic element by a spectroscopic element lens.

A portion of each of the spatially filtered third and fourth quantities of scattered probe beam emanating from the spectroscopic element are each filtered with the wavenumbers of the scattered probe beams to form a third and fourth spatially filtered quantities Through the detector lens. The third and fourth spatially filtered quantities are filtered by the wavenum of the scattered probe beam and are focused by the detector lens to form a line image on a plane containing a linear array of detector pinholes. A portion of each of the spatially filtered third and fourth quantities of the reflected reference beam radiating from the spectroscopic element is filtered with the wavenum of the reflected reference beam to form a third and fourth spatially filtered volume, Through the detector lens. The third and fourth spatially filtered quantities are filtered by the wave number of the reflected reference beam and are focused by the detector lens to form a line image on a plane containing a linear array of detector pin holes.

The third and fourth spatially filtered filtered spectra filtered by the wave number of the reflected reference beam transmitted by the detector pinhole and filtered by the wave number of the scattered probe beam, The intensity of the portion that was measured was measured by a multi-pixel detector consisting of a linear array of pixels as a first array of measured intensity values. The spatially filtered third and fourth positive phases being filtered by the wave number of the reflected reference beam, the first phase-shifted, and the spatially filtered third and fourth positive phases of the reflected reference beam, 4 < / RTI > quantity by the fifth phase shifter. The third and fourth spatially filtered filtered spectra filtered by the wave number of the reflected reference beam transmitted by the detector pinhole and filtered by the wave number of the scattered probe beam, The intensity of a portion of the measured intensity value is measured by a multi-pixel detector as a second array of measured intensity values.

And the spatially filtered third and fourth positive phases are each a second phase-shifted version of the reflected reference beam, filtered with a wavenumber, and filtered with a third spatially filtered amount, And is shifted by an additional radian by the fifth phase shifter to form a fourth quantity. A second phase-shifted version of the reflected reference beam transmitted by the detector pinhole, filtered with a wavenumber, filtered with third and fourth spatially filtered quantities and a wave number of scattered probe beams, The intensity of the overlapping portions of the positive and fourth quantities is measured by a multi-pixel detector as a third array of measured intensity values.

And the spatially filtered third and fourth positive phases are each a third phase-shifted version of the reflected reference beam, filtered with a wavenumber, and filtered with a third spatially filtered amount, And is shifted by an additional radian by the fifth phase shifter to form a fourth quantity. A third phase-shifted version of the reflected reference beam transmitted by the detector pinhole, filtered with a wavenumber, filtered with third and fourth spatially filtered quantities and a wave number of scattered probe beams, The intensity of the overlapping portions of the positive and fourth quantities is measured by a multi-pixel detector as a fourth array of measured intensity values.

In the next step, the first, second, third and fourth arrays of measured intensity values are transmitted to the computer for processing. The elements of the second array of measured intensity values are calculated as a measure of the first array component value of the complex amplitude of the scattered probe beam focused on the plane of the detector pinhole by the light effect from the substantially invalid out- From the corresponding element of the first array of intensity values measured by the computer to produce the intensity values. The elements of the fourth array of measured intensity values are selected such that the light effect from the substantially ineffective out-of-focus image causes the second array component value of the complex amplitude of the in-focus scattered probe beam at the plane of the detector pinhole Is subtracted from the corresponding element of the third array of intensity values measured by the computer to produce a measurement.

The elements of the first and second arrays of the spatially filtered, spatially filtered scattered probe beam are quadrature component values, and thus, the light effect from the substantially ineffective out-of- In the complex constant range of the complex amplitude of the in-focus scattered probe beam. Using computer and computer algorithms known to those skilled in the art, precise two-dimensional and three-dimensional representations of the material of interest can be obtained by first, second and third, respectively, of the measured intensity values obtained by scanning the subject material in one- and two- And a second and a three-dimensional array of a fourth array. Scanning for the target material is accomplished by systematically moving the target materials into one and two dimensions, respectively, with a computer-controlled translator. Computer algorithms may include computer deconvolution and integral-equation inversion techniques known to those of ordinary skill in the art, which re-assemble the component values of the amplitude of the probe beam scattered by the apparatus of the present invention, Should be corrected for the out-of-focus image over which it is desired to surpass.

The signal-to-noise ratio can be adjusted or improved and / or optimized in the third embodiment for the desired complex amplitude measurement. This optimization is achieved by filtering the wavenum of the reflected reference beam focused on the selected detector pinhole by changing the reflection-transmission characteristics of the first, second and third beam splitters, and filtering the spatially filtered third and fourth quantities And adjusting the ratio of the amplitudes of the third and fourth amounts filtered and spatially filtered to the wave number of the scattered probe beam focused on the selected detector pinhole.

According to a fourth embodiment of the present invention, by imaging a broadband, spatially-enlarged, spatially coherent light into a linear array of source pin holes comprising the electronic processing means and apparatus described in the third embodiment, There is provided a method and apparatus for distinguishing a complex amplitude of an in-focus image from an out-of-focus image by means of optimizing and / or improving or adjusting the noise ratio, wherein the source pinhole of the third embodiment is a linear array of source pinholes The spatial filter pinhole of the third embodiment is replaced by a linear array of spatial filter pinholes, and the array of multi-pixel detectors and detector pinholes of the third embodiment is a two-dimensional array of multi-pixel detectors and detector pinholes, Array. The direction of the linear array of source pinholes and the linear array of spatial filter pinholes is perpendicular to the plane defined by the spectroscopic elements. A two-dimensional linear array of detector pinhole and detector pixels is directed from the in-focus plane at the multi-pixel detector to the image of the linear array of source pin holes.

The elements of the array of first and second component values of the amplitude of the spatially filtered scattered probe beam are quadrature component values and thus the light effect from the substantially ineffective out- Represents an accurate measurement of the complex amplitude of the in-focus scattered probe beam in the plane of the detector pinhole within a complex constant range. Using computer and computer algorithms known to those skilled in the art, accurate two-dimensional representation of the two-dimensional portion of the material of interest is obtained substantially without requiring any scanning. The two-dimensional portion is selected by the direction of the linear array of the optical axis of the probe lens and the source pin hole. Using computer and computer algorithms known to those skilled in the art, an accurate three-dimensional representation of an object may be obtained from a three-dimensional array of first, second, third and fourth intensity values through scanning for a material in substantially one dimension . Computer algorithms may include computer deconvolution and integral-equation inversion techniques known to those of ordinary skill in the art, which re-assemble the component values of the amplitude of the probe beam scattered by the apparatus of the present invention, It is necessary to correct for the desired out-of-focus image.

The signal-to-noise ratio obtained in the fourth embodiment can be adjusted or improved and / or optimized for the desired complex amplitude measurement. This adjustment or refinement and / or optimization is effected by modifying the reflection-transmission characteristics of the first, second and third beam splitters to filter the wave number of the reflected reference beam focused on the selected detector pinhole, By adjusting the ratio of the amplitudes of the first and fourth quantities filtered by the amplitudes of the first and fourth quantities and the spatially filtered scattered probe beams focused on the selected detector pinhole and spatially filtered third and fourth quantities.

According to a modification of the fourth embodiment of the present invention, the optical radiation from the part with the broadband, spatially enlarged, and spatially coherent line sources is irradiated onto the source slit including the electron processing means and apparatus described in the fourth embodiment, Focus image from an out-of-focus image, wherein a linear array of source pin holes of the fourth embodiment is replaced by a source slit, and the spatial filter pin hole of the fourth embodiment The linear array was replaced with a spatial filter slit. The direction of the source slit and the spatial filter slit is perpendicular to the plane defined by the spectral element.

The elements of the measured array of wavenumber filtered and spatially filtered scattered probe beam amplitudes of the first and second component values are quadrature component values and thus can be obtained from a substantially invalid out- Focus filter in a plane of a two-dimensional array of detector pinholes with an optical effect and shows an accurate measurement of the complex amplitude of a spatially filtered scattered probe beam within a complex constant range. Using computer algorithms known to those skilled in the art, the exact two-dimensional representation of the two-dimensional portion of the material of interest is obtained by performing any scanning needs. The two-dimensional portion is selected by the respective directions of the optical axis of the probe lens and the source slit. Using computer and computer algorithms known to those skilled in the art, an accurate three-dimensional representation of the material of interest may be obtained by scanning a three-dimensional array of first, second, third and fourth intensity values obtained through scanning on a target material in one dimension / RTI > Scanning for the target material is accomplished by systematically moving the target material in one dimension with a computer controlled translator. Computer algorithms may include computer deconvolution and integral equation inversion techniques known to those of ordinary skill in the art, which must be corrected for the desired out-of-focus image to exceed the compensation achieved by the apparatus of the present invention.

In accordance with the first, second, third and fourth embodiments of the present invention and variations of these embodiments, the apparatus of the present invention is capable of providing a high spatial resolution for each frequency component, A probe lens which can have an enlarged range of < RTI ID = 0.0 > The range in focus can be extended to a range beyond the area defined by the numerical diameter of the probe lens for a single wavelength employing a lens designed to be focal length dependent. The degree of wavelength dependence can be designed within the lens using techniques known to the person skilled in the art. This technique involves the design of a lens multiplet of diffractive material that disperses the dispersion. This lens design also includes a zone plate. If a zone plate is used, the probe lens unit is designed such that most of the optical beam components at a given wavelength are preferably in focus at a degree of the zone plate. The zone plate may be generated by a holographic technique. To obtain the advantage of the magnified range in the focal plane, the beam of the source to the source must be tuned to match the characteristics of the probe lens. That is, it should have a wavelength bandwidth matched to the range at the wavelength of the probe lens.

The first, second, third and fourth embodiments of the present invention and modifications of these embodiments constitute a first embodiment group. The second embodiment group consists of the fifth, sixth, seventh and eighth embodiments and variations of these embodiments. Fifth, sixth, seventh and eighth embodiments and variations of these embodiments correspond to the first, second, third and fourth embodiments and variations of these embodiments, respectively, wherein the axial and longitudinal The first probe lens of the first embodiment group having the chromatic aberration was replaced by the probe lens having the lateral chromatic aberration. The probe lens having the lateral chromatic aberration is arranged such that the line image in the target material and the image point of the line image in the target material arranged close to each other perpendicularly to the optical axis of each probe lens for the embodiment of the second embodiment group and their modifications .

The length of the line image perpendicular to the optical axis of each probe lens is determined by a combination of factors such as the magnitude of the lateral chromatic aberration of each probe lens and the focal length of each probe lens and the optical bandwidth of the source, do.

The third embodiment group consists of the ninth, tenth, eleventh and twelfth embodiments and modifications of these embodiments. The ninth, tenth, eleventh and twelfth embodiments and variants of these embodiments correspond to the first, second, third and fourth embodiments and variants of these embodiments, respectively, wherein the multi- It was not integrated. Missing of the multi-element phase shifter reduces background compensation and degree of reduction from the out-of-focus image for the third embodiment group. The probe lens of the third embodiment group having axial chromatic aberration generates a line image in the object material. The line image is arranged close to the optical axis of the probe lens with the lateral chromatic aberration and the image points of the line image are obtained substantially simultaneously.

The fourth embodiment group consists of the thirteenth, fourteenth, fifteenth and sixteenth embodiments and modifications of these embodiments. The thirteenth, fourteenth, fifteenth, and sixteenth embodiments and variations of these embodiments correspond to the constantly modified configurations of the fifth, sixth, seventh and eighth embodiments and variations of these embodiments, wherein The multi-element phase shifter is not integrated. The omission of the multi-element phase shifter reduces the amount of background compensation and reduction from the out-of-focus image for the fourth embodiment group. The probe lens of the fourth embodiment group having axial chromatic aberration generates a line image in the object material. The line image is arranged close to the optical axis of the probe lens with the lateral chromatic aberration and the image points of the line image are obtained substantially simultaneously.

The fifth embodiment group consists of the seventeenth, eighteenth, nineteenth and twentieth embodiments and modifications of these embodiments. The seventeenth, eighteenth, nineteenth and twentieth embodiments and variants of these embodiments correspond to the constantly modified configurations of the first, second, third and fourth embodiments and variations of these embodiments, respectively, wherein The probe lens with axial chromatic aberration was replaced by a probe lens with substantially no axial chromatic aberration. The image generated in the target material by the embodiment of the fifth embodiment group is usually a point image. The background compensation and the degree of reduction from the out-of-focus image for the embodiment of the fifth embodiment group and its variants are similar to those of the embodiment of the first embodiment and the out-of- This is equivalent to background compensation and reduction. The image pointer for the embodiment of the fifth embodiment group and its modification is obtained sequentially in time.

According to the embodiment of the first embodiment and its variants, the signal-to-noise ratio can be adjusted and / or optimized for the optical frequency component of the carpenter of the source. This is achieved by placing a wavelength filter in the path of the reference and / or the reflected reference beam, preferably the probe and / or the scattered probe beam, and by waveburn-filtering, spatially filtered through different detector pinholes for different wavelengths By adjusting the transmittance of the wavelength filter to have a certain wavelength dependency in order to optimize and / or adjust the ratio of the scattered probe beam. This feature is particularly useful when there is a strong attenuation of the probe through the material of interest and the scattered probe beam.

Fifth Embodiment For each embodiment of the group of the fifth embodiment and its modification, there is a corresponding embodiment for recording information on a target material including a recording medium, and a modification thereof. Each of the corresponding embodiments for recording information and its variants comprises, in composition:

The source and reference mirror systems are interchangeable and the detectors and detector cells are replaced by mirrors and the mirrors are arranged in time and / or direction introduced by the mirrors arranged in combination with the phase-change procedure to produce the desired image on the material of interest Includes apparatus and methods of the corresponding embodiment and its variants, except for spatially dependent phase shifting and temporally and spatially dependent reflectivity to direct light from a source that substantially collides with the mirror itself. The phase-shift procedure is waved to obtain the first, second, third and fourth measured intensity values for each embodiment of the fifth embodiment group and its variants, and the spatially filtered And performs a similar function to the procedure for introducing a sequence of phase shifts in the reflected reference beam.

For any one of the recording embodiments described herein and variations thereof, a single bit binary format is used to store information at a given location in the target material. In any one of the recording embodiments described herein and variations thereof, information storage of a higher density than the information storage density that can be achieved in any one of the recording embodiments and variations thereof, (Radix N) X (radix M) format or radix N format for amplitude and phase information at the storage site of the storage medium.

It will be apparent to those skilled in the art that the sequence of phase shifts in the spatially filtered reflected reference beam to obtain the first, second, third and fourth measured intensity values for the cited embodiment and its variants It should be appreciated that heterodyne detection techniques and phase-sensitive detection can be implemented without departing from the scope and spirit of the present invention. As an example, the phase shift procedure consisting of discrete phase shift values of 0,, and radians can be replaced by a sinusoidal phase shift of the amplitude at the frequency. The first and second component values of the complex amplitude of the spatially filtered spatially filtered scattered probe beam are detected by phase-sensitive detection as first and second harmonics, respectively. This amplitude is selected so that there is a high sensitivity for the detection of both the first and second harmonics. In the second embodiment, the frequency of the reference beam is shifted, for example, by the acousto-optic modulator with respect to the frequency of the probe beam, filtered with a wavenumber, and the first and second of the complex amplitude of the spatially filtered scattered probe beam The component values are obtained by a heterodyne detection technique.

It should be appreciated by those skilled in the art that embodiments for recording information on optical disks and variations thereof may store information in a memory location in a single bit binary format. Those skilled in the art will also appreciate that embodiments and variations thereof for recording information on an optical disk may be implemented in the form of (Radix N) X (Radix M) format for phase and amplitude in memory locations or Radix N format for amplitude, Information can be recorded as transformations in the (base N) X (radix M) format of information to be stored, such as Hilbert transforms.

It should be appreciated by those skilled in the art that stored information can be received by measuring the change in polarization state of the probe beam that is scattered and transmitted by the subject material and that the information can be stored in the medium by the magnetooptical effect.

It will be appreciated by those skilled in the art that the desired scanning of the subject material in each embodiment of the fifth embodiment and its variants and associated recording embodiments can be accomplished with a linear array of source slits or source pinholes And scanning the image of each source pin hole.

The " enabling technology " of the present invention may be applied to any electromagnetic radiation, such as an electron microscope, or an appropriately collimated lens, an imaging lens, an electron beam for use in sound waves suitable for a phase shifter, and a recording medium Should be recognized. For application, the amplitude of the beam is detected instead of the intensity, and the function of generating the square of the amplitude should be done in electronic processing in the detector as follows.

It should be appreciated that the length of the line image in the material of interest can be altered by changing the depth of focus and / or the axial chromatic aberration of the probe lens or the lateral chromatic aberration of the probe lens to the necessary corresponding change in the optical bandwidth of the source .

The line source is spatially coherent in the direction of one of the second and fourth embodiments and each variant thereof, even though the systematic error is generally low when a spatially incoherent line source is used .

The advantages of the first and third embodiment groups for a multi-layer, multi-track optical disc are the same as or much reduced out-of-the-way as obtained in the prior art single-pinhole confocal interference microscopy or holography- The background from the focus image and substantially reduced statistical error is substantially the same imaging of the line portion in the depth direction of the optical disk. Substantially identical imaging of the line portion in the depth direction of the optical disk significantly reduces the sensitivity to movement of the optical disk in the depth direction caused by rotation of the optical disk, dislocation of the optical disk, and / or deviation of the optical disk . Substantially the same imaging of the line portion in the depth direction of the optical disc can also be used to identify the reference surface in the optical disc from the multilayer, information obtained simultaneously from the reference layer, which serves the purpose of registration.

An advantage of the first and third embodiments of providing a single-layer X-ray complex amplitude image for wafers used in the manufacture of integrated circuits is that the prior art single-pinhole confocal interference microscopy or holographic measurement sequence Is substantially the same imaging of the line portion in the depth direction of the wafer with a background and significantly reduced statistical error from the same or a much reduced out-of-focus image as that obtained in < RTI ID = Substantially the same imaging of the line portion in the depth direction of the wafer can be used to significantly reduce the sensitivity of the wafer to movement in the depth direction caused by translation, scanning or vibration of the wafer. Substantially the same imaging of the line portion in the depth direction of the wafer can also be used to identify one side of the wafer and / or the wafer with information obtained simultaneously from multiple depths.

The advantages of the first and third embodiments of providing a tomographic X-ray imaging complex amplitude image for a biological sample are the same as those obtained in the prior art single-pinhole confocal interference microscopy or holographic measurement sequence Is a substantially identical imaging of the line portion in the depth direction of the biological specimen with a background and significantly reduced statistical error from the much reduced out-of-focus image. Substantially the same imaging of the line portion in the depth direction of the biological specimen can be used to significantly reduce the sensitivity of the biological specimen to movement of the biological specimen in the depth direction caused by conversion, scanning or vibration of the biological specimen. Substantially identical imaging of the line portion in the depth direction of the biological specimen can also be used to identify one side of the biological specimen and / or biological specimen as information simultaneously obtained from multiple depths.

The advantages of the first and third embodiments for reading on multi-layer, multi-track optical discs are the same as those obtained in prior art single-pinhole confocal interference microscopy or holographic measurement sequences, Is a substantially simultaneous imaging of the two-dimensional portion of the optical disk with a background and a significantly reduced statistical error from the -of-focus image. One axis of the two-dimensional portion of the optical disk may be parallel to the depth direction of the optical disk and the orthogonal axis of the two-dimensional portion of the optical disk may be parallel to the radial direction of the optical disk or parallel to the tangent to the track of the optical disk. Simultaneous imaging of two-dimensional portions of an optical disk can be used to significantly reduce the sensitivity to movement of the optical disk in the depth and radial directions caused by vibration of the optical disk, non-flatness of the optical disk, and / or rotation of the optical disk . Substantially identical imaging of the two-dimensional portion of the optical disk may be used to identify the track as a reference surface, i.e., information obtained at the same time in multiple layers and multiple depths, with the reference layer, And the reference layer and reference track serve for registration purposes.

An advantage of the group of second and fourth embodiments for reading on a multi-layer, multi-track optical disk is that the same or a much less reduced out-of-focus than that obtained in the prior art single-pinhole confocal interference microscopy or holography- Is a substantially simultaneous imaging of a line portion that is in contact with a layer on the optical disk or on the optical disk with a background and a significantly reduced statistical error from the -of-focus image. Substantially simultaneous imaging of the line portion in contact with the layer on the optical disk or on the optical disk results in the sensitivity to the movement of the optical disk caused by the vibration of the optical disk, the unevenness of the optical disk, and / Can be used to significantly reduce. Substantially simultaneous imaging on an optical disc or on a layer in an optical disc can be used to identify a reference track from simultaneously acquired information from multiple tracks, and the reference track serves for registration purposes.

An advantage of the second and fourth embodiments of providing a single-layer X-ray complex amplitude image for wafers used in the manufacture of integrated circuits is that the prior art single-pinhole confocal interference microscopy or holographic measurement sequence Is substantially the same image for a line portion on or in contact with a wafer in a wafer with a background and significantly reduced statistical error from the same or a much reduced out-of-focus image as that obtained in the previous step. Substantially simultaneous imaging of a line portion on or in a wafer surface can be used to significantly reduce the sensitivity of the wafer to movement caused by translation, scanning, or vibration of the wafer. Substantially simultaneous imaging on the surface in contact with the wafer or within the wafer can also be used to identify the reference plane within the wafer and / or the wafer with information obtained simultaneously from the locations.

An advantage of the first and third embodiments of providing a single-layer X-ray complex amplitude image for wafers used in the manufacture of integrated circuits is that the prior art single-pinhole confocal interference microscopy or holographic measurement sequence Is substantially the same image for a line portion on or in contact with a wafer in a wafer with a background and significantly reduced statistical error from the same or a much reduced out-of-focus image as that obtained in the previous step. One axis of the two-dimensional portion of the wafer is parallel to the depth direction of the wafer. Substantially simultaneous imaging of a line portion on or in a wafer surface can be used to significantly reduce the sensitivity of the wafer to movement caused by translation, scanning, or vibration of the wafer. Substantially simultaneous imaging of a line portion on or in a wafer surface can also be used to identify the reference plane within the wafer and / or the wafer with information obtained simultaneously from the locations.

An advantage of one embodiment of the group of first and third embodiments for providing a tomographic X-ray imaging complex amplitude image for a biological sample is that it is obtained in a measurement sequence by prior art single-pinhole confocal interference microscopy or holography Is substantially the same imaging of the line portion in the depth direction of the biological specimen with a background and significantly reduced statistical error from the same or a much reduced out-of-focus image. One axis of the two-dimensional part of the biological specimen is parallel to the depth direction of the biological specimen. Substantially simultaneous imaging of the line portion in the depth direction of the biological specimen can be used to significantly reduce the sensitivity of the biological specimen to movement of the biological specimen in the depth direction caused by conversion, scanning or vibration of the biological specimen. Substantially simultaneous imaging of the line segments in the depth direction of the biological specimen can also be used to identify one side of the biological specimen and / or the biological specimen as information simultaneously obtained from multiple depths.

An advantage of one embodiment of the group of the second and fourth embodiments for providing a tomographic X-ray imaging complex amplitude image for a biological sample is that it is obtained in the measurement sequence by the prior art single-pinhole confocal interference microscopy or holography A substantially similar statistical error to the background from the out-of-focus image that is the same or much less than that of the biological sample, or a substantially identical image on the biological sample, or a line segment tangent to the surface in the biological sample, Imaging that can be used for noninvasive biopsy. Simultaneous imaging of a line portion on a biological sample or a surface in a biological sample can be used to significantly reduce sensitivity to movement of biological specimens in the depth direction caused by translation, scanning, or vibration of the biological specimen. Simultaneous imaging on a biological sample or a two-dimensional part tangent to a surface within a biological sample can also be used to identify a biological reference location from information obtained from multiple depths simultaneously.

The second and fourth embodiments for reading on a multi-layer, multi-track optical disc. Group Note The advantages of another embodiment are the same as or better than those obtained in the prior art single-pinhole confocal interference microscopy or holography- Is a substantially simultaneous imaging of the two-dimensional portion of the optical disk with the background from the reduced out-of-focus image and a significantly reduced statistical error. One axis of the two-dimensional portion of the optical disk is parallel to the radial direction of the optical disk, and an orthogonal axis of the two-dimensional portion of the optical disk is parallel to the tangent to the track on the optical disk or the optical disk. Substantially simultaneous imaging on or on the optical disc may be used to identify a reference track for read error and track identification for a given track as information obtained simultaneously from multiple tracks, It serves a purpose.

An advantage of the fifth embodiment group for reading on multi-layer, multi-track optical discs is that the out-of-focus or multi-track optical discs have the same or a much smaller reduction than that obtained in the prior art single-pinhole confocal interference microscopy or holography- Dimensional or three-dimensional image of a multi-layer, multi-track optical disc in the background from a focus image.

An advantage of the fifth embodiment group on providing a single-layer x-ray imaging complex amplitude image for a wafer used in the manufacture of an integrated circuit is that in the prior art single-pinhole confocal interference microscopy or holographic measurement sequence Dimensional or three-dimensional image of a multi-layer, multi-track optical disc in the background from an out-of-focus image that is the same or much smaller than that obtained.

An advantage of the fifth embodiment group on providing a tomographic X-ray imaging complex amplitude image for a biological sample, an image that can be used for biopsy of biological specimens is achieved by the prior art single-pinhole confocal interference microscopy or holography Dimensional or three-dimensional image of a biological specimen in the background from an out-of-focus image that is the same or much smaller than that obtained in the measurement sequence.

An advantage of the first four embodiments of the present invention is that the background from the out-of-focus image, which is the same or much smaller than that obtained in the prior art single-pinhole confocal interference microscopy or holographic measurement sequence, Is a substantially simultaneous imaging of the line portion. This substantially simultaneous imaging feature is made possible by the introduction of a technique called " optical wavenumber domain reflectometry (OWDR) " technology. Background reduction is made possible by applying the basic principles of pinhole confocal microscopy to an interferometric measurement system. Substantially simultaneous imaging features enable one-dimensional, two-dimensional and three-dimensional images to be generated with significantly reduced sensitivity to object movement during the measurement process. The problem of migration can place serious limitations on the technologies currently employed in the case of biological system measurements. In PSI and SCLI, which are not incorporated into the techniques disclosed herein, serious limitations may be encountered due to movement caused by vibration. The problem with untracked movement can also place severe limitations on recording and / or reading on multi-layer, multi-track optical discs.

Another advantage of the present invention is that substantially simultaneous or substantially simultaneous detection of the two-dimensional portion in the background from an out-of-focus image that is the same or much less than that obtained in the prior art single-pinhole confocal interference microscopy or holographic- Imaging. This substantially simultaneous imaging feature becomes possible by introducing OWDR technology. Background reduction is made possible by applying the basic principles of pinhole confocal microscopy to an interferometric measurement system. Substantially simultaneous imaging features enable one-dimensional, two-dimensional and three-dimensional images to be generated with significantly reduced sensitivity to object movement during the measurement process. As mentioned above, the problem of movement can impose severe limitations on PSI and SCLI due to the technology currently employed in the case of measurement of biological systems, movement caused by vibration, and PSI and SCLI.

An advantage of embodiments for reading on multi-layer, multi-track optical discs and variations thereof is that out-of-the-box readout is the same or much smaller than that obtained in the prior art single-pinhole confocal interference microscopy or holography- Is a substantially simultaneous imaging of the line portion in the depth direction of the optical disk with a background from the focus image and a significantly reduced statistical error. Substantially simultaneous imaging of the line portion in the depth direction of the optical disk can be used to significantly reduce the sensitivity to the movement of the optical disk in the depth direction caused by rotation, non-flatness, and / or vibration of the optical disk have. Substantially simultaneous imaging of the line portion in the depth direction of the optical disk can be used to generate a reference plane of the optical disk with recording of information in multiple layers, and the reference track serves for registration purposes.

Embodiments of recording on multi-layer, multi-track optical discs and variations thereof, embodiments of groups 1 and 3 of the third embodiment and variants thereof have the advantages of prior art single-pinhole and slit confocal interference microscopes or Is substantially simultaneous imaging of the two-dimensional portion of the optical disk with a background and significantly reduced statistical error from the out-of-focus image that is the same or much smaller than that obtained in the measurement sequence by holography. One axis of the two-dimensional portion of the optical disk is substantially parallel to the depth direction of the optical disk and the orthogonal axis of the two-dimensional portion of the optical disk is substantially parallel to the radial direction of the optical disk, substantially parallel to the tangent of the track of the optical disk, May be in any direction. Substantially simultaneous imaging of the two-dimensional portion of the optical disk can be used to significantly reduce the sensitivity to movement of the optical disk in the depth and orthogonal directions caused by rotation, non-flatness and / or vibration of the optical disk. The substantially simultaneous imaging of the two-dimensional portion of the optical disk can be carried out in a multi-layer and multi-track, reference track serving for registration purposes, and information imaged in the reference layer, / RTI >

Advantages of some embodiments and variations thereof in multi-layer, multi-track optical discs, which correspond to portions of embodiments of the second and fourth groups, and variations thereof, are the prior art single pinhole confocal interference The background from the significantly out-of-focus image, which is the same as or comparable to that produced with successive images using microscopy or holography, and the background on the optical disc or on the layer in the optical disc due to significantly reduced statistical errors Is substantially the same imaging of the line section. Simultaneous imaging of a line section on or in an optical disc can be used to greatly reduce sensitivity to movement of the optical disc and / or the optical disc created by rotation of the transformer of the optical disc.

The advantages of the embodiment corresponding to a portion of the second and fourth groups of embodiments and variations thereof, in the present embodiment of recording on a multi-layer, multi-track optical disc, and variations thereof, The background from the significantly out-of-focus image, which is the same as or comparable to that produced with successive images using focus interference microscopy or holography, and the background on the optical disc or on the optical disc due to significantly reduced statistical errors Lt; / RTI > is substantially the same imaging of the line section tangent to < RTI ID = One axis of the two-dimensional section of the optical disc is essentially parallel to the radial direction on the optical disc and the orthogonal axis of the two-dimensional section of the optical disc yarn is essentially parallel to the tangent of the track on the optical disc or on the optical disc. Simultaneous imaging of a two-dimensional section of the optical disc can be used to significantly reduce the sensitivity of the optical disc motion in the radial direction caused by rotation of the optical disc and / or the transformer of the optical disc. Simultaneous imaging of a two-dimensional section of an optical disc may be used to simultaneously record information at multiple locations on multiple tracks and multiple tracks and to create a reference track for track identification, and the reference track provides an alignment purpose.

The advantage of this embodiment and its variants of writing to a multi-layer, multi-track optical disc, which is an embodiment corresponding to the embodiment of the fifth group, and variations thereof, is that using prior art single pinhole confocal interference microscopy or holography Dimensional, two-dimensional, or three-dimensional image on a multi-layer, multi-track optical disc as the background from a significantly reduced out-of-focus image when compared to a continuous image.

The advantage of the present invention is that the complex scattering amplitude of the object is obtained instead of the magnitude of the scattering amplitude as in the case of PCI and OCT. This is particularly important for the results of computer analysis required to obtain one, two, or three dimensional imaging of a given type of material of interest.

Another advantage is that the computer processing required to obtain the complex scattering amplitudes in one-, two-, and three-dimensional imaging is significantly reduced compared to that required in prior art confocal systems currently applied.

Another advantage is that the computer processing required to acquire a given level using the device, when it is necessary to collect out-of-focus images, which has already been significantly reduced in the apparatus of the present invention, Focus and Scanning Single pinholes and scanning slits are significantly reduced compared to computer processing required in confocal interference microscopy.

Another advantage is that, for a single source pinhole, the contribution of background radiation to statistical noise at the measured complex scattering amplitude over a predetermined transverse distance in the material of interest for a given time interval measurement is less than that of the exemplary embodiment The present invention can obtain the same time interval in the prior art for irradiating a single-pinhole confocal interference microscope with a factor substantially proportional to the square root of the number of independent measurement positions over the axial image distance, , The independence relates to the measured complex scattering amplitude. There is also a similar advantage for a slit confocal interference microscope where the corresponding reduction factor is substantially proportional to the square root of the number of independent measurement positions on the imaged two-dimensional section of the material of interest.

Another advantage is that the contribution of the background radiation to the statistical noise at the measured complex scattering amplitude over a predetermined image axis distance for a given measurement time interval can be reduced in principle to be derived from the magnitude of its complex scattering amplitude, A particularly significant advantage for the case is that the amplitude of the background radiation is relatively large compared to the magnitude of the complex scattering amplitude. This can not be achieved by conventional techniques of scanning a single pinhole or slit confocal eye crossover.

Another advantage is that, for any embodiment of the first group of four embodiments and variations thereof, a substantially one-dimensional scan is required to produce a two-dimensional image, and substantially only two- Dimensional image. ≪ / RTI >

Another advantage is that, for any other embodiment of the four first embodiment groups and variations thereof, a scan in substantially only one dimension is required to produce a three-dimensional image.

In summary, the instant invention's apparatus reduces (1) systematic errors, (2) reduces statistical errors, (3) reduces the dynamic range requirement for detectors that process electrons and record media, ) Increase the density of data stored on the optical disc, (5) reduce the computer processing required to generate either one-dimensional, two-dimensional or three-dimensional, and (6) And / or (7) be operable upon imaging through a turbid medium.

In general, one or more of these features may be performed in operation in parallel.

The present invention relates to optical and acoustic imaging, and includes the use of optical and acoustic images to perform optical data storage and retrieval and to perform precision measurements on biological samples, wafers, integrated circuits, optical disks, and other samples .

In the drawings, like reference characters designate like elements in the several views.

Figures la-1n, taken together, are schematic representations of a light path between subsystems 80 and 81, 81 and 82, 81 and 83, 82 and 81a, 83 and 81a, and 81a and 84; A path of an electronic signal from the computer 118 to the translators 116 and the phase shifters 44 of the subsystem 83; And a first embodiment group of FIG. 1A for illustrating the path of an electronic signal from the detector 114 to the computer 118 of the subsystem 84;

Figure 1B illustrates subsystem 80, and the plane of Figure 1B is perpendicular to the plane of Figure 1A;

Figure 1C illustrates subsystem 81, wherein the plane of Figure 1C is perpendicular to the plane of Figure 1A;

1D illustrates subsystem 82 for the case of a probe beam entering sub-system 82, the plane of FIG. 1D being perpendicular to the plane of FIG. 1A; FIG.

Figure 1e illustrates subsystem 83 for the case of a reference beam entering sub-system 83, the plane of Figure 1e being perpendicular to the plane of Figure 1a;

1F illustrates subsystem 82 for the case of a probe beam exiting subsystem 82, the plane of FIG. 1F being perpendicular to the plane of FIG. 1A;

Figure 1G illustrates subsystem 83 for the case of a reference beam exiting subsystem 83, the plane of Figure 1G being perpendicular to the plane of Figure 1A;

Figure 1h illustrates subsystem 81a for the case of a probe beam entering sub-system 81a, the plane of Figure 1h being perpendicular to the plane of Figure 1a;

Figure 1i illustrates subsystem 81a for the case of a reference beam entering sub-system 81a, the plane of Figure 1i being perpendicular to the plane of Figure 1a;

1J illustrates subsystem 84 for the case of a probe beam entering sub-system 84, and the plane of FIG. 1J is perpendicular to the plane of FIG. 1A;

1K illustrates subsystem 84 for the case of a reference beam entering sub-system 84, and the plane of FIG. 1K is perpendicular to the plane of FIG. 1A.

FIG. 11 illustrates subsystem 82 for the case of an out-of-focus beam in subsystem 82 resulting from scattering and / or reflection of light in subsystem 82, Is perpendicular to the plane of Fig.

1 m describes a subsystem 81a for the case of an out-of-focus beam in subsystem 81a resulting from light scattering and / or reflection in subsystem 82, and the plane of FIG. Is perpendicular to the plane of Fig.

Figure 1n illustrates subsystem 84 for the case of a background light beam entering subsystem 84 and the plane of Figure 1n is perpendicular to the plane of Figure 1a.

1a-1c are schematic representations of the beam splitter 100 and the subsystem 82aa, the beam splitter 100 and the subsystem 83aa, the sub- The paths of the respective electronic signals 132 and 133 to the optical path between the systems 82aa and 85 and the subsystems 83aa and 95 and the transducer 116 and the transducer 44 of the subsystem 83aa, Lt; RTI ID = 0.0 > 1A < / RTI > illustrating a preferred embodiment of the present invention;

Figure lab illustrates a subsystem 82aa for the case of a probe beam entering subsystem 82aa, wherein the plane of Figure lab is perpendicular to the plane of Figure laa;

Fig. Lac describes a subsystem 85 for the case of a probe beam entering sub-system 85, the plane of Fig. Lac being perpendicular to the plane of Fig. Laa;

Figure 1ad illustrates subsystem 83aa for the case of a reference beam entering sub-system 83aa, the plane of Figure 1ad being perpendicular to the plane of Figure laa;

1 ae explains subsystem 95 for the case of a reference beam entering sub-system 95, the plane of FIG. 1 ae being perpendicular to the plane of FIG. 1 aa;

Figure 1 af illustrates subsystem 85 for the case of a scattering probe beam exiting subsystem 85, the plane of Figure 1 af being perpendicular to the plane of Figure laa;

Figure 1ag illustrates a subsystem 82aa for the case of a scattering probe beam exiting subsystem 82aa, wherein the plane of Figure 1ag is perpendicular to the plane of Figure laa;

Figure 1ah illustrates subsystem 95 for the case of a reflected reference beam exiting subsystem 95, and the plane of Figure 1ah is perpendicular to the plane of Figure laa;

Figure 1ai illustrates subsystem 83aa for the case of a reflected reference beam exiting subsystem 83aa, and the plane of Figure 1ai is perpendicular to the plane of Figure laa;

Figures 2a-2f, taken together, are schematic representations of a light path between subsystems 80a and 81, 81 and 82, 81 and 83, 82 and 81b, 83 and 81b, and 81b and 84a; A path of an electronic signal from the computer 118 to the translators 116 and the phase shifters 44 of the subsystem 83; And a second embodiment of the present invention for FIG. 2A showing the path of an electronic signal from the detector 114a to the computer 118 of the subsystem 84a.

Fig. 2b illustrates subsystem 80a, the plane of Fig. 2b being perpendicular to the plane of Fig. 2a, and the linear array of pinholes 8a with the direction of the line source in the plane of Fig. 2a;

Fig. 2C illustrates subsystem 81b for the case of irradiated light entering subsystem 81b, the plane of Fig. 2C being perpendicular to the plane of Fig. 2A, and the linear array of pinholes 18b in the plane of Fig. There is;

Figure 2d illustrates subsystem 81b for the case of a reference beam entering sub-system 81b, the plane of Figure 2d being perpendicular to the plane of Figure 2a, and the linearity of pinhole 18b There is an array;

Figure 2e illustrates subsystem 84a for the case of a probe beam entering sub-system 84a, the plane of Figure 2e being perpendicular to the plane of Figure 2a;

Figure 2f illustrates subsystem 84a for the case of a reference beam entering subsystem 84a, the plane of Figure 2f being perpendicular to the plane of Figure 2a;

Figure 2aa schematically illustrates a beam splitter 100 and a subsystem 82aa, a beam splitter 100 and a subsystem 83aa, subsystems 82aa and 85a, ) And the paths of the respective electronic signals 132 and 133 to the transducer 116 and to the phase shifter 44 of the subsystem 83aa, as well as the optical path between the subsystems 83aa and 95, Described below is a sixth preferred embodiment of the present invention from a second group of embodiments;

Figures 3a-3l taken together are schematic representations of the optical path between the subsystems 80 and 81, 80 and 81c, 81 and 82, 81c and 83a, 82 and 81a, 83a and 81a and 81a and 84; A path of an electronic signal from the computer 118 to the translator 116 and the phase shifter 44 of the subsystem 83a; And FIG. 3A, which illustrates the path of an electronic signal from the detector 114 of the subsystem 84 to the computer 118, according to a third preferred embodiment of the present invention;

Figure 3b illustrates subsystem 80, and the plane of Figure 3b is perpendicular to the plane of Figure 3a;

Figure 3c illustrates subsystem 81, the plane of Figure 3c is perpendicular to the plane of Figure 3a;

Figure 3d illustrates subsystem 82 for the case of a probe beam entering sub-system 82, the plane of Figure 3d being perpendicular to the plane of Figure 3a;

Figure 3e illustrates the subsystem 81c and the plane of Figure 3e is parallel to the plane of Figure 3a;

Figure 3f illustrates subsystem 83a for the case of a reference beam entering subsystem 83a and the plane of Figure 3f is parallel to the plane of Figure 3a and for purposes of illustration only phase shifters 34 and 34a Are rotated 90 degrees with respect to the axes 3a and 3c, respectively.

Figure 3g illustrates subsystem 82 for the case of a probe beam entering sub-system 82, the plane of Figure 3g being perpendicular to the plane of Figure 3a;

Figure 3h illustrates subsystem 83a for the case of a reference beam entering subsystem 83a and the plane of Figure 3h is perpendicular to the plane of Figure 3a and for purposes of illustration only phase shifters 34 and 34a Are rotated 90 degrees with respect to the axes 3a and 3c, respectively.

Figure 3i illustrates subsystem 81a for the case of a probe beam entering sub-system 81a, the plane of Figure 3i being perpendicular to the plane of Figure 3a;

3J illustrates subsystem 81a for the case of a reference beam entering sub-system 81a, and the plane of FIG. 3j is perpendicular to the plane of FIG. 3A;

Figure 3k illustrates subsystem 84 for the case of a probe beam entering sub-system 84, the plane of Figure 3k being perpendicular to the plane of Figure 3a;

Figure 31 illustrates subsystem 84 for the case of a reference beam entering sub-system 84, and the plane of Figure 31 is perpendicular to the plane of Figure 3A;

3A-3B are schematic illustrations in combination with any one of FIGS. 3A-3L, showing a beam splitter 100 and a subsystem 82aa, a beam splitter 100 and a subsystem 83ab, a subsystem 82aa And 85 and the paths of the respective electronic signals 132 and 133 to the phase shifters 44 of the translators 116 and 83ab with the optical paths between the subsystems 83ab and 95 A seventh embodiment of the present invention, which is preferable from the second embodiment group for Fig.

Figure 3ab illustrates a subsystem 83ab for the case of a reflected reference beam entering sub-system 83ab, the plane of Figure 3ab parallel to the plane of Figure 3aa, and for purposes of illustration only, phase shifter 34b And 34a are rotated 90 degrees with respect to the axes 3b and 3f, respectively;

Figures 4a-4f, taken together, are schematic representations of an optical path between subsystems 80a and 81, 80a and 81c, 81 and 82, 81c and 83a, 82 and 81b, 83a and 81b, and 81b and 84a; A path of an electronic signal from the computer 118 to the translators 116 and the phase shifters 44 of the subsystem 83a; And FIG. 4A, which illustrates the path of an electronic signal from the detector 114a of the subsystem 84a to the computer 118, according to a fourth preferred embodiment of the present invention;

Figure 4b illustrates subsystem 80a, and the plane of Figure 4b is perpendicular to the plane of Figure 4a;

Figure 4c illustrates subsystem 81b for the case of a scattering probe beam entering sub-system 81b, the plane of Figure 4c being perpendicular to the plane of Figure 4a;

4d illustrates subsystem 81b for the case of a reflected reference beam entering sub-system 81b, and the plane of FIG. 4d is perpendicular to the plane of FIG. 4a;

Figure 4e illustrates subsystem 84a for the case of a scattering probe beam entering sub-system 84a, and the plane of Figure 4e is perpendicular to the plane of Figure 4a;

4f illustrates subsystem 84a for the case of a reflected reference beam entering subsystem 84a, and the plane of FIG. 4f is perpendicular to the plane of FIG. 4a;

Figure 4aa is a schematic representation in combination with any one of Figures 4a-4f, including beam splitter 100 and subsystem 82aa, beam splitter 100 and subsystem 83ab, subsystems 82aa and 85, And the optical path between the subsystems 83ab and 95 and the path of each electronic signal 132 and 133 to the phase shifter 44 of the translators 116 and 83ab Described next is a preferred eighth embodiment of the present invention from the second embodiment group;

Figure 5 is a geometrical view of a reflective confocal microscope with four imaging sections;

Figure 6 is a graph showing the amplitude of the out-of-focus image in the horizontal plane of the spatial filter pinhole according to the four embodiments of the present invention mentioned and variations of the embodiments;

Fig. 7 is a graph showing the reference beam amplitudes reflected from the horizontal plane of the spatial filter pinhole according to the four embodiments of the present invention mentioned and variations of the embodiments; Fig.

Figures 8a-8c relate to lithography and its application in integrated circuit fabrication, Figure 8a is a schematic of a lithographic exposure system using a confocal microscopy system;

Figures 8b and 8c are flowcharts illustrating the manufacturing steps of the integrated circuit; And

9 is a schematic diagram of a mask inspection system using a confocal microscopy system.

The present invention is based on the idea that reflection and / or scattering by the volume elements of the three-dimensional object material space from the complex amplitude of the background light generated by the double-printed out-of-focus image structure before, Allowing for the separation of the complex amplitude of the emitted light. The embodied tomography technique may separate a certain complex amplitude signal in the image plane from the " background " and " foreground " complex amplitude signals generated by various mechanisms. Such background and foreground complex amplitude signals may include (1) a section image of the out-of-focus material other than the imaged line section or the two-dimensional section, (2) scattering of the desired amplitude signal, (3) Scattering of signals originating from sources other than the dimension section, and / or (4) heat radiation. The scattering site and the heat radiation source may be located in a line section or a front, one side, and / or a rear space of a two-dimensional section of the object under investigation.

The technique of the present invention is performed with one of two different discrimination levels against an out-of-focus image. At the first level (level 1), the impulse response function of the imaging subsystem of the inventive device is processed by either one of two orthogonal planes, respectively, by introducing a one-dimensional pattern of phase shifts in the pills of a representative imaging system. At the second level (level 2), the impulse response function of the imaging subsection of the inventive device is processed with both orthogonal planes by introducing a two-dimensional pattern of phase shifts in the pills of a representative imaging subsystem. Level 2 discrimination leads to more effective discrimination of out-of-focus images from images in in-focus than level 1 discrimination, both for systematic and statistical errors. The level 1 and level 2 discrimination can be performed for any of the preferred embodiments described.

The permissive technique of the present invention, which is common to each preferred embodiment of the instant invention arrayed in either level 1 or level 2, will now be described only for the preferred embodiment with level 1 discrimination.

Level 1 discrimination is based on the detailed orientation of the orthogonal plane in which the impulse response function of the imaging subsystem is processed. The choice of the orientation of the orthogonal planes in which the impulse response function of the imaging subsystem is processed greatly affects the degree of reduction of the background beam effect on the statistical errors achieved in the inventive apparatus.

Referring to the figures with a sphere volume, Figures 1A-1N show a schematic form of a first preferred embodiment of the instant invention. 1A-1n, a preferred embodiment of the present invention includes a beam splitter 100, an object material 112, a translator 116, a reference mirror 120, dispersion detector elements 130a and 130b, , And a detector (114). This configuration is known as the Michelson interferometer technology and is shown as a simple example. With the same technology as the product by polarized Mickelson interferometer and C. Zanoni (VDI Berichte NR. 749, pp. 93-106, 1989), entitled "Differential Interferometer Arrays for Distance and Angular Measuring: Principle, Advantage and Application" Other forms of known interferometers may be combined with the apparatus of Figures la-ln without significantly deviating from the spirit and scope of the first preferred embodiment of the present invention.

In a first preferred embodiment, the orientation of the plane in which the impulse response function of the imaging subsystem is processed is perpendicular to the plane of Fig. 1A and parallel to the optical axis of the imaging subsystem.

FIG. 1B illustrates one embodiment of the subsystem 80 shown in FIG. 1A in a schematic form. The plane of FIG. 1B is perpendicular to the plane of FIG. 1A. For the first preferred embodiment, the light source 10 preferably comprises a laser, or a preferably polarized laser beam, which traverses the source surface of a pseudo-source of scattered or spatially coherent radiation, most preferably a superirradiant laser, Point source or an incoherent radiation source spatially. The light source 10 emits an incident beam 2 that is aligned with the optical axis 3 of the subsystem 80. The light beam 2 is incident on the focusing lens 6 and focused on the pinhole 8 in the image plane 7, as shown in Fig. 1B. A light beam 12 composed of a plurality of light beams 12-1, -2, -3 and -4 branches off from the pinhole 8 and has an optical axis aligned with the optical axis 3 And enters the lens 16. The light beam 12 exits from the lens 16 into a parallelized light beam 12A composed of the light beams 12A-1, -2, -3, -4 and enters the phase shifter 14. The phase shifter 14 is composed of rectangular phase shifters 14-1, -2, -3, -4 whose typical optical axis is positioned so as to be parallel to the optical axis 3 of the subsystem 80. [ The number of phase shifts can be any suitable number that is an integer. The embodiment shown in FIG. 1B is for the case of four phase shifters sufficient to clearly show the relationship between the components of the inventive apparatus. The parallel light beams 12A-1, -2, -3 and -4 pass through the phase shifters 14-1, -2, -3 and -4, respectively, and the light beams 12B from the phase shifter 14 (12B-1, -2, -3, -4), respectively. Each of the phase shifters 14-2 and 14-4 introduces a phase shift that is larger than the phase shift introduced by each of the phase shifters 14-1 and 14-3 by a radian and the phase shifters 14-1 and 14-3 ) Are the same.

In FIG. 1A, the light beam 12B exits the subsystem 80 and enters the subsystem 81. FIG. 1C, the light beam 12B enters the lens 26 having an optical axis aligned with the optical axis 3 of the subsystem 81 and is incident on the light beam 12C-1, -2, -3, -4 Resulting in a configured light beam 12C. The plane of Fig. 1C is perpendicular to the plane of Fig. 1A. The lens 26 focuses the light beam 12C from the image plane 17 to the image point 18. The light beam 12C emerges from the image point 18 into a light beam 22 consisting of light beams 22-1, -2-3-4. The light beam 22 enters a lens 36 having an optical axis aligned with the optical axis 3 of the subsystem 81. The light beam 22 exits the lens 36 and exits the subsystem 81 with the collimated light beam 22A consisting of the light beams 22A-1, -2-3-4.

1A, the light beam 22A is partially transmitted as a light beam P22B composed of the light beams P22B-1, -2, -3, -4 by the beam splitter 100, 0.0 > 82 < / RTI >

In Fig. 1D, the light beam P22B enters the phase shifter 24 composed of phase shifters 24-1, -2, -3, -4. The plane of Figure 1d is perpendicular to the plane of Figure 1a. The phase shifter 24 consists of the same number of elements as the phase shifter 14 and is shown together in Fig.

The light beams P22B-1, -2, -3 and -4 pass through the phase shifters 24-1, -2, -3 and -4, respectively, and pass through the light beams P22C-1, And a light beam P22C, respectively. The phase shift introduced by the phase shifters 24-1 and 24-3 is a phase shift of the same value that is larger than the phase shift introduced by any one of the phase shifters 24-2 and 24-4 by a radian, -2 and 24-4) are phase shifts of the same value.

The sum of the phase shifts introduced by each pair of phase shifters 14-1 and 24-1, 14-2 and 24-2, 14-3 and 24-3, and 14-4 and 24-4 is in radians. Therefore, there is no net relative phase shift between any two of the light beams P22C-1, -2, -3, -4. The light beam P22C is a light beam P22D composed of the light beams P22D-1, -2, -3, -4 and is focused on the image plane 28 from the image plane 27 of the object material 112 And passes through the focused lens 46 to form a line image. The axis of the line image is substantially parallel to the optical axis 3 of the imaging subsystem 82. The length of the image line is a combination of factors such as the depth of focus and the chromatic aberration of the probe lens 46 and the optical bandwidth of the source 10. [ . The line section can be cut into one or more surfaces of the subject material or placed on the surface of the subject material. The optical axis of the lens 46 is aligned with the optical axis 3 of the subsystem 82.

1A, a light beam 22A is partially reflected by a beam splitter 100 into a light beam R22B composed of light beams R22B-1, -2, -3, -4. The light beam R22B enters the subsystem 83 shown in Fig. 1E. The plane of Figure 1e is perpendicular to the plane of Figure 1a. As shown in FIG. 1E, the light beam R22B enters the phase shifter 34 composed of phase shifters 34-1, -2, -3, -4. The phase shifter 34 includes the same number of elements as the phase shifter 14 and is shown together in Fig. After passing through the phase shifter 34, the light beam R22B passes through the phase shifter 44 to exit to the light beam R22C composed of the light beams R22C-1, -2, -3, -4. The abnormal variation introduced by the phase shifter 44 is controlled by the signal 132 from the computer 118. The phase shift introduced by phase shifters 34-1 and 34-3 is a phase shift of the same value that is greater than the phase shift introduced by either one of phase shifters 34-2 or 34-4 by a radian, -2 and 34-4) are phase shifts of the same value. Therefore, there is no net relative phase shift between any two of the light beams R22C-1, -2, -3, -4. The light beam R22C passes through the lens 56 with a light beam R22D composed of light beams R22D-1, -2, -3, -4. The light beam R22D is focused by the lens 56 from the image plane 37 on the reference mirror 120 to the image point 38. The optical axis of the lens 56 is aligned with the optical axis 3a of the subsystem 83.

1D, a part of the light beam P22D (see FIG. 1D) is divided into a plurality of light beams P32-1, -2, -3, -4 including a scattering probe beam P32, / RTI > is reflected and / or scattered by the material of interest in the line image focused on the line image. The plane of FIG. 1F is perpendicular to the plane of FIG. 1A. The scattering probe beam P32 diverges from the image point 28 of the image plane 27 and enters the lens 46. 1F, the scattering probe beam P32 emerges from the lens 46 as a parallelized scattering probe beam P32A consisting of the light beams P32A-1, -2, -3, -4 .

The light beams P32A-1, -2, -3 and -4 pass through the phase shifters 24-1, -2, -3 and -4, respectively, and pass through the light beams P32B-1, -4). The light beams P32B-1, -2, -3, -4 include a scattering probe beam P32B exiting the subsystem 82. [ The phase shift introduced by the phase shifters 24-1 and 24-3 is a phase shift of the same value that is larger than the phase shift introduced by any one of the phase shifters 24-2 and 24-4 by a radian, -2 and 24-4) are phase shifts of the same value.

In FIG. 1G, the light beam R22D (see FIG. 1E) is reflected by the reference mirror 120 to the reflection reference beam R32 composed of the light beams R32-1, -2, -3, -4. The plane of FIG. 1G is perpendicular to the plane of FIG. 1A. The reflective reference beam R32 diverges from the image point 38 of the image plane 37 and enters the lens 56. As shown in Fig. 1G, the reflection reference beam R32 is emitted from the lens 56 to a parallelized reflection reference beam R32A composed of the light beams R32A-1, -2, -3, -4 . The light beams R32A-1, -2, -3, -4 first pass through the phase shifter 44 and then are reflected by the reflection reference beams R32B-1, -2, -3, And passes through the phase shifters 34-4, -3, -2, -1 so as to go out to the R32B. The phase shift introduced by the phase shifter 44 is controlled by the signal 132 from the computer 118. The phase shift introduced by the phase shifters 34-1 and 34-3 is a phase shift of the same value that is larger than the phase shift introduced by the phase shifters 34-2 and 34-4 by? And 34-4 are phase shifts of the same value. The light beams R32B-1, -2, -3, -4 include a light beam R32B exiting the subsystem 83. [

It is shown in FIG. 1A that the scattering probe beam P32B is partially reflected by the beam splitter 100 into a scattering probe beam P32C consisting of the light beams P32C-1, -2, -3, -4. The scattering probe beam P32C enters the subsystem 81a shown in FIG. 1H. The plane of FIG. 1h is perpendicular to the plane of FIG. 1A. 1H, the scattering probe beam P32C enters a lens 26a having an optical axis aligned with the optical axis 3a of the subsystem 81a, and is incident on a scattering probe composed of the light beams P32D-1, -2, -3, -4. Beam P32D. The lens 26a focuses the scattering probe beam P32D on the pinhole 18a of the image plane 17a. A portion of the scattering probe beam P32D emerges from the pinhole 18a into a spatially filtered scattering probe beam P42 consisting of the light beams P42-1, -2, -3, -4. The scattering probe beam P42 enters the lens 36a having an optical axis aligned with the optical axis 3a of the subsystem 81a. The spatially filtered scattering probe beam P42 exits the lens 36a and is collimated by a collimated spatially filtered scattering probe beam P42A consisting of light beams P42A-1, -2, -3, -4. And exits system 81a.

1A, the reflection reference beam R32B is partially transmitted to the reflection reference beam R32C composed of the light beams R32C-1, -2, -3, -4 by the beam splitter 100 do. The reflection reference beam R32C enters the subsystem 81a shown in Fig. 1i. The plane of FIG. 1I is perpendicular to the plane of FIG. 1A. In Fig. 1I, the reflection reference beam R32C enters the lens 26a and emerges as a reflection reference beam R32D composed of the light beams R32D-1, -2, -3, -4. The lens 26a focuses the reflection reference beam R32D to the pinhole 18a of the image plane 17a. A portion of the reflection reference beam R32D comes out of the pinhole 18a into a spatially filtered reference beam R42 composed of the light beams R42-1, -2, -3, -4. The spatially filtered reflected reference beam R42 enters lens 36a. The spatially filtered reflected reference beam R42 exits the lens 36a and is collimated by a collimated spatially filtered reflected reference beam R42A consisting of light beams R42A-1, -2, -3, -4 And exits system 81a.

It is shown in FIG. 1A that the spatially filtered scattering probe beam P42A preferably impinges on the dispersive element 130a, which is a reflective diffraction grating. A portion of the spatially filtered scattering probe beam P42A is diffracted by the first dispersion detector element 130a into the scattering probe beam P42B in the plane of FIG. 1A. The scattering probe beam P42B preferably impinges on the second dispersion detector element 130b which is the transmission diffraction grating. A portion of the scattering probe beam P42B is waved by the second dispersion detector element 130b in the plane of FIG. 1A and diffracted into a spatially filtered scattering probe beam P42C. The paths of only one frequency component of the beams P42B and P42C are shown in Fig. 1A, although the beams P42B and P42C are composed of the spectrum of the optical frequency components and thus are angularly distributed in the plane of Fig. The depicted paths are typical. Examples of one optical frequency component alone for the beams P42B and P42C may be filtered by wavenumbers without introducing complexity that is not appropriate to Figure 1a and the accompanying figures without departing from the spirit or scope of the present invention And allows display of the main characteristics of the subsystem 84 with respect to the spatially filtered scattering probe beam P42C.

The wavenumber filtered and spatially filtered beam P42C enters the subsystem 84 shown in FIG. 1J. The plane of FIG. 1J is perpendicular to the plane of FIG. 1A. 1J, a wavenumber-filtered and spatially filtered beam P42C passes through a lens 66 having an optical axis aligned with the optical axis 3d of the subsystem 84 and passes through the optical beam P42D- 1, -2, -3, -4), and is output as a spatially filtered beam P42D. And the spatially filtered beam P42D is focused by the lens 66 onto the image point 48 of the image plane 47. In this way, The position of the image point 48 of the image plane 47 and the position of the image point 48 on the linear array of detector pinholes located in the image plane 47 are wavenely filtered by the dispersion detector elements 130a and 130b , And the optical frequency of the spatially filtered beam P42D. A portion of the light beam passing through the linear array of detector pinholes is detected by a detector comprised of a linear array of pixels, such as a multi-pixel detector 114, preferably a linear array CCD.

The collision of the spatially filtered reflected reference beam R42A with the reflective detector element 130a is shown in FIG. 1A. A portion of the spatially filtered reflected reference beam R42A is diffracted by the scatter detector element 130a in the plane of FIG. 1A into a reflected reference beam R42B. And the reflection reference beam R42B collides with the second dispersion detector element 130b. A portion of the reflective reference beam R42B is waved by the second dispersion detector element 130b in the plane of FIG. 1A and is diffracted into a spatially filtered reflected reference beam R42C. The paths of only one optical frequency component to the beams R42B and R42C are shown in Fig. 1A, although the beams R42B and R42C are composed of the spectrum of the optical frequency components and thus are scattered in the plane of Fig. The depicted paths are typical. An example of only one optical frequency component for the beams R42B and R42C can be filtered by wavenumbers without introducing complexity that is not appropriate for Figure 1a and the accompanying Figures without departing from the spirit or scope of the present invention. And allows the display of the main characteristics of the section 84 to the spatially filtered reflection reference beam R42C.

The wavenumber filtered, spatially filtered reflected reference beam R42C enters the subsystem 84 shown in Figure 1K. The plane of Figure 1k is perpendicular to the plane of Figure 1a. 1K, the wave-filtered and spatially filtered reflected reference beam R42C passes through lens 66 and is filtered with a wave number comprised of light beams R42D-1, -2, -3, -4, Filtered reference beam R42D. 1K, the spatially filtered reflected reference beam R42D is focused by the lens 66 onto the image point 48 of the image plane 47 . The position of the image point 48 of the image plane 47 and the position of the image point 48 on the linear array of detector pinholes located in the image plane 47 are filtered with a wavenumber, It depends on the optical frequency of the beam R42D. A portion of the light beam passing through the linear array of detector pinholes is detected by the multi-pixel detector 114.

A portion of the light beam P22 (see FIG. 1D) is reflected by the object material at the "out-of-focus" image point 58 of the out-of- 1, -2, -3, -4). The plane of FIG. 11 is perpendicular to the plane of FIG. 1A. The background beam B52 branches off from the out-of-focus image point 58 and enters the lens 46. As shown in FIG. 11, the background beam B52 emerges from the lens 46 as a substantially parallelized background beam B52A consisting of the light beams B52A-1, -2, -3, -4. The light beams B52A-1, -2, -3 and -4 pass through the phase shifters 24-4, 24-3, 24-2 and 24-1, respectively, and the light beams B52B-1 and -2 , -3, -4), respectively. The light beams B52B-1, -2, -3, -4 include the background beam B52B. The phase shift introduced by the phase shifters 24-1 and 24-3 is a phase shift of the same value that is larger than the phase shift introduced by any one of the phase shifters 24-2 and 24-4 by < RTI ID = 0.0 > 24-2 and 24-4) are phase shifts of the same value.

As shown in Fig. 1A, the background beam B52B is partially reflected by the beam splitter 100 into the background beam B52C composed of the light beams B52C-1, -2, -3, -4. The background beam B52C enters the subsystem 81a shown in FIG. 1M and passes through the lens 26a to the background beam B52D. The background beam B52D is composed of the light sources B52D-1, -2, -3, -4. The plane of Figure 1m is perpendicular to the plane of Figure 1a. The background beam B52D is focused on the image point 68 of the out-of-focus image plane 67 displaced from the image plane 17a by the lens 26a.

The background beam B52D is out of focus in the image plane 17a and therefore only a small portion of the out-of-focus background beam B52D for each frequency component of the background beam B52D is transmitted by the pinhole 18a . A small portion of the out-of-focus background beam B52D is transmitted to the background beam B62 consisting of the light beams B62-1, -2, -3, -4 spatially filtered by the pinhole 18a. A portion of the spatially filtered background beam B62 is incident on a collimated spatially filtered background beam B62A-1, B62A-1, -2, -3, -4 that substantially hits the lens 36a and is composed of light beams B62A- ). The spatially filtered background beam B62A exits the subsystem 81a with the spatially filtered background beam B62A.

It is shown in FIG. 1A that the spatially filtered background beam B62A strikes the dispersion detector element 130a. A portion of the spatially filtered background beam B62A is diffracted by the first diffusing detector element 130a into the background beam B62B in the plane of FIG. 1A. The background beam B62B strikes the second diffusion detector element 130b. A portion of the background beam B62B is waved by the second dispersion detector element 130b in the plane of Figure 1A and diffracted by the spatially filtered background beam B62C. Beams B62B and B62C are comprised of a spectrum of optical frequency components and thus are angularly dispersed in the plane of FIG. 1A, and the path of only one optical frequency component to beams B62B and B62C is shown in FIG. 1A. The spatially filtered background filtered beam B62C enters the subsystem 84 shown in FIG. 1n. In Fig. 1n, the wavenumber filtered, spatially filtered background beam B62C passes through the lens 66 and is filtered in a wave number, leaving the spatially filtered background beam B62D. The spatially filtered background beam B62D is focused on the image point 48 of the image plane 47 by the lens 66. The spatial frequency of the filtered background beam B62D, The position of the image point 48 of the image plane 47 is filtered by the wave number and depends on the optical frequency of the spatially filtered background beam B62D. A portion of the light beam that has passed through the linear array of detector pinholes is detected by the multi-pixel detector 114.

The operation of the inventive device described in FIGS. 1A-1N is based on the acquisition of four consecutive intensity measurements by each of the pillars of the detector 114. FIG. A linear array of four consecutive intensity values (I ₁ , I ₂ , I ₃ , and I ₄ ) represents a continuous phase shift (a total of a reference beam including an ideal transformation produced by passing through the phase shifter 44 in both directions) Is obtained by a detector 114 having a phase shifter 44 that introduces a phase shift (x ₀ , x ₀ + pi, x ₀ + pi / 2, and x ₀ + 3 pi / 2 radians) ₀ is a fixed value of the phase shift. (Of course, the functions of phase shifters 34 and 34 may be combined into a single phase shifter controlled by computer 118.) A linear array of four intensity values I ₁ , I ₂ , I ₃ , and I ₄ Is sent as a signal 131 to the computer 118 either in digital or analog format for subsequent processing. A conventional conversion circuit, for example, an analog-to-digital converter, may be used to convert a linear array of four intensity values (I ₁ , I ₂ , I ₃ , and I ₄ ) ). ≪ / RTI > Phase shifting of phase shifter 44 may be performed by computer 118 after the sequence has been described above to produce equations 12a and 12b or subsequently generated by computer 118 according to the same sequence described above in equation 36 132, respectively. The phase shifter 44 may be a phase shifter of the type subsequently described herein for use in wideband operation with respect to the electrooptic type or optical wavelength. The intensity differences I ₁ -I ₂ and I ₃ -I ₄ are then computed at the computer 118 and these differences are filtered into a wavenumber, spatially filtered scattered probe beam P42D, And an interference cross term having a substantially higher efficiency for a representative corresponding optical frequency component between the complex amplitudes of the spatially filtered reflected reference beam R42D.

The complex amplitude of the spatially filtered and spatially filtered scattering probe beam P42D (see FIG. 1J) and the complex amplitude of the spatially filtered and spatially filtered reflected reference beam R42D (see FIG. 1K) The relatively high efficiency for isolation of interference cross-terminations is the result of two system characteristics. The first system property is defined as the complexity of the complex amplitude of the complex amplitude of the spatially filtered scattered probe beam P42D filtered by the wave number in the image plane 47 and the wave number filtered and spatially filtered reflected reference beam R42D The spatial distribution is substantially the same for any phase transformation introduced by phase shifter 44. [ The second system characteristic is the difference between the complex amplitude of the scattered probe beam P42D filtered by the wave number in the image plane 47 and the spatially filtered scattered probe beam P42D and the complex amplitude of the wave filtered and spatially filtered reflected reference beam R42D The interference cross term changes the signal when the phase shift introduced by the phase shifter 44 is increased or decreased by?, 3 ?, ... radians. An interference cross term between the complex amplitude of the wave-filtered and spatially filtered scattering probe beam P42D in the image plane 47 and the complex amplitude of the wave-filtered and spatially filtered reflected reference beam R42D, when the phase shift introduced by 44 to be increased or decreased by the radians π, 3π, ..., due to the change signal, wherein the interference is a cross intensity difference (I ₁ -I _2, and I ₃ -I ₄ ). However, all non-interference cross terms such as, for example, a wavenumber filtered and spatially filtered scattered probe beam P42D, a wavenumber filtered and spatially filtered background beam B62D (see FIG. 1n) And the intensity of the spatially filtered reflected reference beam R42D is not canceled by the intensity differences I ₁ -I ₂ , and I ₃ -I ₄ . A preferred system property is a feature that has a confocal interference microscope in common and is referred to below as " confocal interferometer system property ".

I _{1 -} I ₂ , and I ₃ - I ₂ , as a result of the confocal interferometer system property, for the wave front filtered by the image plane 47 and spatially filtered background beam B 62 D I ₄ includes the interference cross-port between the complex amplitude of the spatially filtered scattered background beam B 62 D and the complex amplitude of the spatially filtered reflected reference beam R 42 D filtered by the complex amplitude and frequency of the spatially filtered scattered background beam B 62 D. However, the magnitude of the interference cross-term between the complex amplitude of the filtered and spatially filtered background beam B62D in the image plane 47 and the complex amplitude of the wave-filtered and spatially filtered reflected reference beam R42D Is significantly reduced as compared to the corresponding interference cross term in the confocal interference microscope on the Pelsel by the pixel comparison of the prior art.

The intensity difference (I ₁ -I ₂ , I ₂ -I ₂ , I ₂ -I ₂ , I ₃ -I ₂ , And I ₃ -I ₄ , the interference amplitude between the complex amplitude of the wave-wise filtered and spatially filtered scattering probe beam P42D and the complex amplitude of the wave-filtered and spatially filtered reflected reference beam R42D, There are two interference cross terms of the interference cross term between the complex amplitude of the wavenumber filtered and spatially filtered background beam B62D and the complex amplitude of the wavenumber filtered and spatially filtered reflected reference beam R42D. Interferences between the complex amplitude of the wavenumber filtered and spatially filtered background beam B62D and the complex amplitude of the spatially filtered scattered probe beam P42D filtered by the wavenumber interference intensity difference as a result of the confocal interferometer system property (I ₁ -I ₂ , and I ₃ -I ₄ ).

The interference crossing between the complex amplitude of the wavefront filtered and spatially filtered background beam B62D in the image plane 47 and the complex amplitude of the wave-filtered and spatially filtered reflected reference beam R42D, -Ob -Focus is representative of the background from the image. The inventive apparatus compared to the prior art interference confocal microscopy system is characterized in that the complex amplitude of the wavenumber filtered and spatially filtered background beam B62D and the complex amplitude of the wavefront filtered and spatially filtered reflected reference beam R42D While the size of the interference cross term between complex amplitudes is generally reduced in magnitude in the image plane 47, the prior art has shown that the complexity of the spatially filtered scattered probe beam P42D, filtered in the image plane 47, There is substantially no reduction in magnitude and in the magnitude of the interference cross term between the complex amplitude of the filtered and spatially filtered reflection reference beam R42D. The reduction of the interference cross-term between the complex amplitude of the wavenumber filtered and spatially filtered background beam B62D in the image plane 47 and the complex amplitude of the wavenumber filtered and spatially filtered reflection reference beam R42D results in an image Partially follows the fact that the amplitude of the beam decreases with increasing distance of the plane. This characteristic is the basis of the reduced background in prior art confocal interference microscopes. However, in the inventive apparatus, the complex amplitude of the spatially filtered background beam B62D, filtered by the wave number in the image plane 47, and the complex amplitude of the spatially filtered reflected reference beam R42D, The reduction in the magnitude of the interference cross-term between amplitudes is enhanced compared to that achieved in prior art confocal interference microscopes.

The enhanced reduction mentioned in the previous paragraph is realized in the presence of phase shifters 14, 24, and 34. The phase shifters 14,24 and 34 are arranged in a frequency domain that is filtered by the wave number in the image plane 47 and includes a spatially filtered scattered probe beam P42D, a wave filtered, spatially filtered reflected interference beam R42D, Changes the spatial characteristics of the complex amplitude of the spatially filtered and spatially filtered background beam B62D. The spatial characteristics of the complex amplitude of the spatially filtered scattered probe beam P42D and the spatially filtered reflected reference beam R42D filtered by the waveguides 14, 24 and 34 The modified spatial distribution of the representative complex amplitudes in the image plane 47 is substantially the same.

This characteristic is defined as the intensity difference I (I) between the complex amplitude of the wave-filtered and spatially filtered scattering probe beam P42D and the complex amplitude of the spatially filtered reflected reference beam R42D, _1- I ₂ , and I ₃ -I ₄ ).

However, the complex amplitude of the spatially filtered background beam B62D, which is filtered in the image plane 47 and filtered by the wave number, and the complex amplitude of the spatially filtered reflected reference beam R42D, The distribution is clearly different. The spatially filtered and spatially filtered reflected reference beam R42D is an asymmetric function within the image plane 47, with respect to the center of the filtered reference spatially filtered reflected reference beam R42D. In contrast, the spatially filtered background beam B62D, which is filtered with a wavenumber, is filtered with the resulting wave number interfering with the complex amplitude of the spatially filtered reflected reference beam R42D, (B52D-1, -2, - < / RTI > < RTI ID = 0.0 > - B52D-1) < / RTI > that typically filters only a small relative change across the space of the image of the spatially filtered reflected reference beam R42D, 3, or B52D-4). Thus, interference between the complex amplitude of the spatially filtered background beam B62D filtered in the image plane 47 and the complex amplitude of the spatially filtered spectrally filtered reflected reference beam R42D The spatial distribution of the cross terms is mainly filtered into the image plane 47 and asymmetrically distributed with respect to the center of the spatially filtered reflected reference beam R42D.

For the intensity value recorded by a single pixel of the detector 114, the complex amplitude of the spatially filtered background beam B62D, filtered by the wave number, filtered by the wave number, and filtered spatially filtered reflected reference beam R42D ) Is the integral of the interference cross term along the space of the image formed by the spatially filtered reflected reference beam R42D, filtered in wave number in the image plane 47. The interference cross term < RTI ID = 0.0 > Integrating the asymmetric function over the centered space interval with respect to the asymmetric contraction makes equally zero. Thus, for intensity values recorded by a single pixel of the detector 114, the complex amplitude of the spatially filtered background beam B62D filtered with a wavenumber, the complex amplitude of the spatially filtered background beam B62D, The net distribution of the interference cross term between the complex amplitudes of the reference signal R42D is significantly reduced above that obtained with the prior art confocal interference microscope.

For the intensity values recorded by the single pixel of the detector 114, the complex amplitude of the spatially filtered background beam B62D filtered in the image plane 47, and the complex amplitude of the spatially filtered background beam B62D, The reduction of the interference cross term between the complex amplitudes of the reflected reference beam R42D results in statistical errors as well as reduced systematic errors. The interference amplitude between the complex amplitude of the spatially filtered background beam B62D filtered in the image plane 47 and the complex amplitude of the spatially filtered and spatially filtered reflected reference beam R42D is reduced The statistical error is reduced since it causes a reduced number of photoelectrons generated at each pixel of the detector 114 compared to the prior art. Since the statistical uncertainty of the integrated charge and the resulting output signal are related to the square root of the integrated number of the photoelectrons generated at each pixel of the detector, the statistical error in the output signal is considerably reduced for the devices in Figs. do.

Thus, the statistical error per image point of the imaged line section of the material of interest obtained with the apparatus of the present invention is significantly smaller than that obtained at the same time interval for the prior art confocal interference microscope for two reasons . The first reason is that in the prior art interferometric confocal microscopes, the imaged line sections are scanned at the same time intervals in the imaging section of the imaging device to obtain the intensity difference of the array corresponding to the intensity difference of the array obtained simultaneously in the inventive device At a time interval that reduces the time spent at each image point by a plurality of image points in the image. This is due to the fact that when compared to that obtained in prior art interferometric confocal microscopes, the image of the line section imaged by the factor proportional to the square root of the plurality of independent image points in the imaged line section for the apparatus of the present invention It improves the statistical accuracy of images composed of points. The rationale for the second reason is the complex amplitude of the spatially filtered background beam B62D filtered in the image plane 47 and the complex amplitude of the filtered and spatially filtered reflected reference beam R42D Is significantly reduced with respect to that obtained with the corresponding interfering cross term in the prior art confocal interference microscope as recorded in the paragraph of the previous description. These two reasons are based on the fact that the statistical error introduced by the amplitude of the out-of-focus image, when considering the statistical accuracy of the image of the line section of the material of interest obtained at the same interval of time, In the device of the present invention with respect to the corresponding statistical error introduced by the amplitude of the out-of-focus image of the present invention.

The effect of the out-of-focus image, that is, the correction for the systematic error, which is beyond the compensation obtained by the apparatus of the first embodiment, is made by using computer and computer deconvolution and integral equation inverse techniques, Are known to those skilled in the art to reverse the equations according to equations (32a) and (32b) described above.

The signal-to-noise ratio is adjusted as a function of the wavelength of the source optical frequency component to produce, for example, the signal-to-noise ratio to the first order independence of the wavelength. In general, the amplitude of the wavelength filtered spatially filtered scattered probe beam P42D normalized to the corresponding optical frequency component of the amplitude of the probe beam P22D, before entering the target material 112, As the depth of the image point 28 into the object material 112 increases, the wavelength dependent on the transmission of the probe beam P22D and the scattered probe beam P32 in the object material 112 and the change in the numerical aperture of the probe lens 46 Will vary with the wavelength due to. Also, the ratio of the amplitude of the wavelength filtered, spatially filtered and scattered probe beam P42D to the amplitude of the wavelength filtered and spatially filtered background beam B62D is proportional to the amplitude of the image point 28 into the object material 112 As the depth increases, it will usually decrease. The change in the signal-to-noise ratio is due to the amplitude of the wavelength-filtered, spatially filtered and scattered probe beam P42D normalized to the corresponding optical frequency component of the amplitude of the probe beam P22D before entering into the object material 112 It will usually change accordingly. The effect of such a factor of signal-to-noise ratio can be achieved by placing the wavelength filter in the probe beam subsystem 82 and / or in the reference mirror subsystem 83, more preferably in the reference mirror subsystem 83, The detailed wavelength dependency is plotted for the wavelength filtered, spatially filtered scattering probe beam P42D and wavelength filtered, transmitted through each detector pinhole for different wavelengths according to equation (39) And / or < / RTI > equalized to the ratio of the reflected reference beam R42D.

It is known in the detailed description of the embodiments that there is no net relative phase shift between any light beam P22C-1, -2, -3, -4. This feature makes it possible to achieve the following objects, which are disclosed in the detailed description of the first embodiment: the object is achieved by means of the reference mirrors 14 and 24, respectively, which are not substantially changed by the presence of the phase shifters 14 and 24 and the phase shifters 14 and 34, Generates a conjugate image of the pinhole 8 in the image plane 27 on the object material 112 and the image plane 28 on the object material 112, To produce a substantial change in the image in the image plane 17a, 47 in the conjugate relationship to the image pointer 38 above the mirror 120. [

Also, the insight into the interrelationship between the phase shifters 14, 24, 34 is obtained by considering what will happen if the phase shifter 14 is removed in the first embodiment. In this case, the wavenumber filtered, spatially filtered reflection reference beam R42D is filtered with a wavenum in the image plane 47 and is filtered by the image plane 47 (FIG. 47) without substantial change in the spatially filtered background beam B62D. ) Asymmetric function to a symmetric function. Thus, the spatial variance of the interference cross-term between the spatially filtered reflected reference beam R32D and the complex amplitude and frequency of the spatially filtered background beam B62D is filtered by the And is mainly composed of a symmetric dispersion about the center of the spatially filtered reflection reference beam R42D. However, the integration of the symmetric function on the spatial interspace concentrated on the axis of the symmetric function is usually not zero, but is recorded by the given pixel of the detector 114 at the image point 48 to that obtained in the prior art confocal interference microscope There is practically no decrease in the strength value.

The computer 118 applies a control signal 133 to the translators 116 to determine the position of the target object 112 at the image point 28, To allow the system to " scan " the desired line, planar, or volume section of the target material 112 by positioning the tip of the material 112. The required line, plane, or volume section of the material of interest may cut or include one or more surfaces of the material of interest.

In a first preferred embodiment of the present invention, level 1 discrimination is obtained by adjusting the pulse response function of the imaging subsystem of the inventive device in the orthogonal plane to a plane defined by the dispersion detector elements 130a, 130b. Further, the level 1 type discrimination is obtained in a variant of the first preferred embodiment, in which the apparatus of modification and the electronic processing means comprise a phase shifter 14, 24, 34 rotated by? / 2 radian for each optical axis, Is substantially the same as the example. In a variation of the first preferred embodiment, the reduction of the system effect of the out-of-focus image is the same as that of the first preferred embodiment. Also, in a modification of the first preferred embodiment, the stabilizing effect due to the out-of-focus image is reduced below that obtained in the prior art confocal interference microscope, but is usually not as effective as obtained in the apparatus of the first preferred embodiment.

2A-2F, FIG. 2A illustrates a second embodiment of the present invention and a second embodiment of the source subsystem 80a, subsystem 81b, and detector subsystem 84a from a first group of embodiments, A modification of the second embodiment of the present invention, which is preferably configured for scoping, is described in structural form. Since the same elements have been described above with respect to Figures 1a-1n, the same reference numerals are used in Figures 2a-2f. The deformation in subsystem 80a shown in Fig. 2b is in the region of source 10a, which is now preferably configured as a broadband, spatial incoherent line source, more preferably a lamp filament or laser diode array , Also in the region of the pinhole 8 of the first embodiment, which now consists of a linear array of source pinholes 8a aligned with the image of the line source 10a formed by the lens 6, preferably now. The modification in the subsystem 81b shown in Figures 2c and 2d can be combined with the linear array of spatial filter pinholes 18b in the subsystem 81b to the exchange pinhole 18a in the subsystem 81a of the first embodiment . The deformation in the subsystem 84a shown in Figures 2e and 2f is in the region of the detector 114a in which a linear array of pinholes in the image plane 47 of the first embodiment is now preferably The detector 114 of the first embodiment, which is a two-dimensional array and has a linear array of pixels, is now preferably a detector 114a comprised of a two-dimensional array of pixels.

In Fig. 2b, the linear array of source pinhole 8a and source 10a is aligned perpendicular to the plane of Fig. 2b, and the plane of Fig. 2b is perpendicular to the plane of Fig. 2a. In Figures 2c and 2d, the linear array of spatial filter pinholes 18b are aligned perpendicular to the planes of Figures 2c and 2d, and Figures 2c and 2d are perpendicular to the plane of Figure 2a. In Figures 2e and 2f, the two-dimensional array of detector pinholes and the two-dimensional array of detector pixels are aligned perpendicular to the plane of Figures 2e and 2f.

The remainder of the second embodiment illustrated in Figs. 2A-2F is preferably the same as that described for the corresponding aspect of the first preferred embodiment of the description of Figs. 1A-1N.

Level 1 discrimination in the second preferred embodiment of the present invention is obtained by adjusting the pulse response function of the imaging subsystem of the inventive device in an orthogonal plane to a plane defined by the dispersion detector elements 130a, 130b. Further, the level 1 type discrimination is obtained in the first modified example of the second preferred embodiment, wherein the apparatus of the first modified example of the second preferred embodiment is characterized in that for the second preferred embodiment, (14, 24, 34) which rotate by a predetermined distance. The reduction of the systematic effect of the out-of-focus image in the first variant of the second preferred embodiment is the same as in the second preferred embodiment. Also, the stabilizing effect due to the out-of-focus image in the first variant of the second preferred embodiment is reduced below that obtained with the prior art confocal interference microscope, but is usually as effective as that obtained with the apparatus of the second preferred embodiment It is not.

A second variant of the second preferred embodiment is described in which the apparatus of the second variant and the electron processing means comprise a spatial filter pinhole 18a and source pinhole 8a of the second preferred embodiment replaced by a source slit and a spatial filter slit Is substantially the same with respect to the second preferred embodiment except for the linear array. The reduction of the systematic effect of the out-of-focus image for the second variant of the second preferred embodiment is the same as that obtained in the second preferred embodiment of the present invention. In addition, in the second variant of the second preferred embodiment, the stabilizing effect due to the out-of-focus image is further reduced than that obtained in the prior art confocal interference microscope, but is usually not as effective as that obtained in the apparatus of the second preferred embodiment.

The use of a linear array of spatial pinholes and a linear array of source pinholes, such as in the first and second variants of the second preferred embodiment and second preferred embodiment, instead of each slit, allows a limited scan of the material of interest to be performed in a two- . ≪ / RTI > The direction of the limited scan is the direction of the image of the array of source pin holes in the material of interest. The limited scan increases due to the space between the pinholes in the direction of the image of the linear array of source pinholes in the material of interest. In addition, the high sensitivity to wavenumped, spatially filtered scattered probe beam is determined by the condition that the space between the pinholes in the direction of the image of the linear array of source pinholes in the material of interest is continuously represented in equation (54) Followed by.

The number of steps of the limited scan is determined by the ratio of the space between each resolution of each imaging subsystem and the image of the two consecutive source pinholes in the target material. In practice, the number of steps in the limited scan will be significantly less than the number of pin holes in the linear array of source pin holes and spatial filter pin holes. Using the apparatus of the first variant of the second preferred embodiment and the second variant with a linear array of source pinholes and spatial filter pinholes, the two-dimensional representation of the material part of interest can be obtained substantially without scanning.

3A-3I, an alternative third embodiment of the present invention is illustrated from a first group of embodiments in which the reference of the first preferred embodiment and the path of the probe beam are modified for the purpose of improving and optimizing the signal-to-noise ratio. The apparatus and the electron processing means of the third embodiment are substantially the same as the additional optical means forming the interferometer of the first embodiment in the first preferred embodiment so that the ratio of the amplitude of the reflection reference and the scattering probe beam can be adjusted. The optical element of the third preferred embodiment performs the same operation as the elements similarly denoted in the first preferred embodiment, and the electronic processing apparatus of the third preferred embodiment performs the same operation as the similarly-indicated electronic operation of the first preferred embodiment. The ratio of the amplitude of the wave-filtered, spatially filtered and reflected reference and scattering probe beams is adjusted by changing the transmission / reflection coefficients of the beam splitters 100, 100a, 100b described in FIGS.

A third preferred embodiment of the present invention includes a beam splitter 100, 100a, 100b, an object material 112, a translator 116, a reference mirror 120, a dispersion detector element < RTI ID = (130a, 130b) and a detector (114). This shape is known as a type of Michelson interferometer and is illustrated by a simple description. Other forms of interferometry known in the art as described in the literature titled " Differential Interferometer Arrangements for Distance and Angle Measurement: Principles, Advantages, and Applications ", in the polarized Mickelson interferometer and C. Zanoni, 3 < / RTI > without deviating greatly from the spirit and meaning of the first and third embodiments.

The direction of the plane in which the pulse response function of the imaging subsystem is adjusted in the third preferred embodiment is perpendicular to the plane of Fig.

FIG. 3B illustrates, in an approximate form, an embodiment of the subsystem 80 shown in FIG. 3A. The plane of Figure 3b is perpendicular to the plane of Figure 3a. For a third preferred embodiment, the light source 10 is preferably a spatial incoherent or point source of radiation through the face of the source, more preferably a laser or coherent or partially coherent source of radiation Source, and most preferably a super-emission laser, and is preferably polarized. The light source 10 emits an input beam 2 aligned with the optical axis 3 of the subsystem 80. 3B, the light beam 2 enters the focusing lens 6 and is focused at the pinhole 8 in the image plane 7. As shown in FIG. A light beam 12 composed of a plurality of light beams 12-1, -2, -3, -4 diverges and enters a lens 16 having an optical axis aligned with the optical axis 3 of the subsystem 80 . The light beam 12 exits from the lens 16 such as a parallel light beam 12A composed of the light beams 12A-1, -2, -3, -4 and enters the phase shifter 14. [ The phase shifter 14 consists of quadrature phase shifters 14-1, -2, -3, -4 which are positioned so that their respective optical axes are parallel to the optical axis 3 of the subsystem 80. Remember that the number of phase shifters is any suitable number 2m, m, which is an integer. The example shown in FIG. 3B is the case where m = 2, which is a case where four phase shifters are sufficient to clearly show the relationship between the components of the apparatus of the present invention. The parallel light beams 12A-1, -2, -3, and -4 pass through the phase shifters 14-1, -2, -3, -4, respectively, , -2, -3, -4) from the phase shifter 14. Each of the phase shifters 14-2 and 14-4 introduces a phase shift larger by? Radian than the phase shift introduced by each of the phase shifters 14-1 and 14-3, and the phase shifters 14-1 and 14- 3) are the same.

3A, the light beam 12B exits the subsystem 80 and is partially transmitted by the beam splitter 100a as a light beam P12B composed of the light beams P12B-1, -2, -3, -4. The light beam P12B enters the subsystem 81. 3C, the light beam P12B enters the lens 26 and emerges as a light beam P12C composed of the light beams P12C-1, -2, -3, -4. The plane of Figure 3c is perpendicular to the plane of Figure 3a. The lens 26 focuses the light beam P12C on the image point 18 in the image plane 17. The light beam P12C comes out of the image point 18 as a light beam P22 composed of the light beams P22-1, -2, -3, -4. The light beam P22 enters a lens 36 having an optical axis aligned with the optical axis 3 of the subsystem 81. [ The light beam P22 comes out of the lens 36 and leaves the subsystem 81 as a parallel light beam P22A composed of the light beams P12A-1, -2, -3, -4.

3A, the light beam P22A is partially transmitted by the beam splitter 100 as a light beam P22B composed of the light beams P12B-1, -2, -3, -4. The plane of Figure 3d is perpendicular to the plane of Figure 3a.

In Fig. 3D, the light beam P22B impinges on the phase shifter 24 composed of the elements 24-1, -2, -3, -4. The phase shifter 24 is composed of the same number of phase shifters 14 and 2m elements and is shown as m = 2 in Fig. The light beams P12B-1, -2, -3 and -4 pass through the phase shifters 24-1, -2, -3 and -4, respectively, and pass through the light beams P12C-1, As the light beam P22C. The phase shift introduced to the phase shifters 24-1 and 24-3 is a phase shift introduced by either one of the phase shifters 24-2 and 24-4 and the phase shifters 24-2 and 24-4 having the same values, ), Which is greater than < RTI ID = 0.0 > radian. ≪ / RTI > There is no purely related phase shift between any two of the light beams P12C-1, -2, -3, -4. The light beam P22C is focused on the focused light beams P12D-1, -2, -3, -4 (not shown) to form a line image centered at the image point 28 in the image plane 27 in the object material 112 And passes through the probe lens 46 as a light beam P22D. The axis of the line image is substantially parallel to the optical axis 3 of the imaging subsystem 82. The length of the line image is determined by a combination of factors such as the chromatic aberration of the probe lens 46 and the depth of focus, both of which can be adjusted to the optical width of the source 10. The line portion is cut through one or more surfaces of the material of interest or placed on the surface of the material of interest. The optical axis of the lens 46 is aligned with the optical axis 3 of the subsystem 82.

3A, the light beam 12b is partially reflected by the beam splitter 100a as a light beam R12B composed of the light beams R12B-1, -2, -3, -4. The light beam R12B enters the subsystem 81c shown in Fig. 3E. The plane of Figure 3e is parallel to the plane of Figure 3a.

3E, the light beam R12B enters the lens 26c and emerges as a light beam R12C composed of the light beams R12C-1, -2, -3, -4. The light beams R12B-1, -2, -3, -4 are spatially separated in a plane perpendicular to the plane of Fig. 3E and superimposed within the view shown in Fig. The lens 26c has an optical axis aligned with the optical axis 3b of the subsystem 81c. The lens 26c associated with the plane mirror 120c aligns the focal point of the light beam R12C to the image point 18c in the image plane 17c. The light beam R12C emerges from the image point 18c as a light beam R22 composed of the light beams R22-1, -2, -3, -4. The light beams R22-1, -2, -3, -4 appear spatially separated in a plane perpendicular to the plane of Fig. 3e and overlap and co-extend in the view shown in Fig. 3e. The light beam R22 enters a lens 36c having an optical axis aligned with the optical axis 3c of the subsystem 81c. The light beam R22 exits from the lens 36c and exits the subsystem 81c as a parallel light beam R22A composed of the light beams R22A-1, -2, -3, -4. The light beams R22A-1, -2, -3, -4 appear spatially separated in a plane perpendicular to the plane of Fig. 3e and overlap and coextend within the view shown in Fig. 3e.

As shown in FIG. 3A, the light beam R22A enters subsystem 83a after exiting subsystem 81c. The subsystem 83a shown in FIG. 3F is composed of a lens 56a, a reference mirror 12, a beam splitter 100b, and phase shifters 34, 34a, and 44. The plane of Figure 3f is parallel to the plane of Figure 3a. The phase shifter 34a composed of the phase shifter elements 34 and the phase shifter elements 34a-1, -2, -3, -4 constituted by the phase shifter elements 34-1, -2, -3, 3/2 with respect to the optical axes 3a and 3c, respectively, for the purpose of making description and tracking of the optical beams R22A, R22B, R22C and R22D through a simpler subsystem 83a without deviating from the spirit and meaning of the embodiment Radian rotation is described in Fig. 3f. The light beam R22A composed of the light beams R22A-1, -2, -3, -4 and the light beam R22B composed of the light beams R22B-1, -2, -3, 2, -3, -4) and the optical beams R22C and R22D-1, -2, -3 (as shown in FIG. 3F) which are rotated by? / 2 radian with respect to the light beam R22C- , -4) is described in FIG. 3F as being rotated by? / 2 radians with respect to the optical axis 3a. In the subsystem 83a, the light beam R22A impinges on the phase shifter 34a containing the same number of elements as the phase shifter 14 and 2m. The light beam R22A passes through the phase shifter 34a as a light beam R22B. And the light beam R22B is partially reflected as the light beam R22C. The phase shift introduced by phase systers 34a-1 and 34a-3 is the same value, which is larger than the phase shift introduced by any one of phase shifters 34a-2 and 34a-4 by? Radians, 2, 34a-4) have the same value. There is no pure relative phase shift between any two of the light beams R22C-1, -2, -3, -4. The light beam R22C passes through the lens 56a as a light beam R22D. Is focused by the lens 56a onto the image point 38 in the image plane 37 above the light beam R22D reference mirror 120. [ The optical axis of the lens 56a is aligned with the optical axis 3a of the subsystem 83a.

3G, a part of the light beam P22D (see FIG. 3D) is irradiated from the image point 28 as a plurality of light beams P32-1, -2, -3, -4 including a scattering probe beam P32 Reflected and / or scattered by material 112. The plane of Figure 3g is perpendicular to the plane of Figure 3a. The scattering probe beam P32 is dispersed from the image point 28 in the image plane 27 and enters the lens 46. As shown in Fig. 3G, the scattering flood beam P32 comes out of the lens 46 as a parallel scattering probe beam P32A consisting of the light beams P22A-1, -2, -3, -4. The light beams P22A-1, -2, -3 and -4 pass through the phase shifters 24-4, -3, -2 and -1, respectively, and pass through the light beams P22B-1, ). The light beams P22B-1, -2, -3, -4 include a scattering probe beam P32B exiting the subsystem 82. The phase shifts introduced by the phase shifters 24-1 and 24-3 are phase shifted by phase shifters introduced by any one of the phase shifters 24-2 and 24-4 to the phase shifters 24-2 and 24-4 Lt; RTI ID = 0.0 > radian < / RTI >

In Fig. 3H, the light beam R22D (see Fig. 3F) is reflected by the reference mirror 120 as a reflection reference beam R32 composed of the light beams R32-1, -2, -3, -4. The subsystem shown in Figure 3h is comprised of a lens 56a, a reference mirror 120, a beam splitter 100b, and phase shifters 34,34a, 44. The phase shifter 34a composed of the phase shifter elements 34 and the phase shifter elements 34a-1, -2, -3, -4 constituted by the phase shifter elements 34-1, -2, -3, 3 radians with respect to the optical axes 3a and 3c for the purpose of making the tracking or explanation of the optical beams R32, R32A and R32B through the simpler subsystem 83a without deviating from the spirit and meaning of the three embodiments Is illustrated in Figure 3h. Therefore, the light beam R32C composed of the light beam R32A, the light beam R32B composed of the light beams R32B-1, -2, -3, -4 and the light beams R32C-1, -2, -3, Is rotated by? / 2 with respect to the optical axis 3a and is described in Fig. 3H. The plane of Figure 3h is parallel to the plane of Figure 3a. The reflection criterion R32 is dispersed from the image point 38 in the image plane 37 and enters the lens 56a. As shown in Fig. 3H, the reflection reference beam R32 comes out of the lens 56a like a parallel light beam R32A. The light beams R32A-1, -2, -3, -4 first pass through the phase shifter 44 and then through the phase shifts 34-4, -3, -2, -1, 1, -2, -3, -4). The phase shift introduced by the phase shifter 44 is controlled by the signal 132 from the computer 118. The phase shift introduced by the phase shifters 34-1 and 34-3 is shifted to the phase shifters 34-2 and 34-4 having the phase shifts introduced by either one of the phase shifters 34-2 and 34-4 and the same value Lt; RTI ID = 0.0 > radian < / RTI > The reflection reference beam R32B exits the subsystem 83a.

3A, the portion of the scattering probe beam P32B is reflected by the beam splitter 100 as a plurality of light beams P32C-1, -2, -3, -4 include a scattering probe beam P32C . The scattering probe beam P32C enters the subsystem 81a shown in FIG. 3A. In Fig. 3i, the scattering probe beam P32D appears as composed of the light beam P32D-1, -2, -3, -4. The plane of Figure 3i is perpendicular to the plane of Figure 3a. The lens 36a has an optical axis aligned with the optical axis 3a of the subsystem 81a. The lens 26a aligns the focus of the scattering probe beam P32D with the spatial filter pinhole 18a in the image plane 17a. The scattering probe beam P32D appears from the spatial filter pinhole 18a as a spatially filtered scattering probe beam P42 consisting of the light beams P42-1, -2, -3, -4. The spatially filtered scattering probe beam P42 enters a lens 36a having an optical axis aligned with the optical axis 3a of the subsystem 81a. The spatially filtered scattering probe beam P42 is incident on the subsystem 81a as a parallel spatially filtered scattering probe beam P42A that emerges from the lens 36a and is composed of the light beams P42A-1, -2, -3, -4. ).

3A, the reflection reference beam R32B is partially transmitted by the beam splitter 100 like the reflection reference beam R32C composed of the light beams R32C-1, -2, -3, -4 . The reflection reference beam R32C enters the subsystem 81a shown in Fig. 3J. The plane of Figure 3j is perpendicular to the plane of Figure 3a. In Fig. 3J, the reflection reference beam R32C enters the lens 26a and appears as a reflection reference beam R32D composed of the light beams R32D-1, -2, -3, -4. The lens 26a aligns the focal point of the reflection reference beam R32D with the spatial filter pinhole 18a in the image punctiform surface 17a. The reflection reference beam R32D appears from the spatial filter pinhole 18a as a spatially filtered reference beam R42 composed of the light beams R42-1, -2, -3, -4. The spatially filtered reflected reference beam R42 enters lens 36a. The spatially filtered reflected reference beam R42A exits the subsystem 81a as a parallel spatially filtered reflected reference beam R42A consisting of the light beams R42A-1, -2, -3, -4.

The spatially filtered scattering probe beam P42A is shown in Figure 3A to strike the dispersive element 130a, which is preferably a diffraction grating. The spatially filtered scattering probe beam P42A is diffracted in the plane of Fig. 3A by the scattering detector element 130a along the scattering probe beam P42B. The scattering beam element 130b preferably strikes on the transmission diffraction grating phosphor 2 scattering detector beam element 130b. The scattering probe beam P42B is diffracted in the plane of FIG. 3A by the second scattering detector beam element 130b along the spatially filtered scattered probe beam P42C filtered by the wave number. The path of only one frequency component of the beams P42B and P42C is shown in Fig. 3A, although the beams P42B and P42C are comprised of the spectrum of the optical frequency components and the angles are distributed in the plane of Fig. 3A. The depicted path is typical. The description of only one optical frequency component for the beams P42B and P42C can be used without undue departure from the spirit and the meaning of the present invention and without undue complexity as in Fig. 3a and wavenumber filtered, Permits the listing of important characteristics of the sus system 84 with respect to the probe beam P42C.

The spectrally filtered, spatially filtered beam P42C enters the subsystem 84 shown in Figure 3K. The plane of Figure 3k is perpendicular to the plane of Figure 3a. 3K, the spatially filtered beam P42C filtered through the lens 66 having an optical axis aligned with the stiffness axis 3d of the subsystem 84 and passing through the optical beam P42D- 1, -2, -3, -4), and along the spatially filtered beam P42D. The wave-filtered, spatially filtered beam P42D, described with only one optical frequency component, is focused by the lens 66 into the image plane 47 into the image plane 48. [ The position of the image point 48 in the image plane 47 and therefore the position of the image point 48 on the linear array of detector pinholes located in the image plane 47 due to dispersion detector elements 130a and 130b Is subject to the optical frequency of the wave-filtered, spatially filtered beam P42D. The light beam portion passing through the array of pin holes is detected by a detector comprised of a linear array of pixels, such as a detector 114, more preferably a linear array CCD.

The spatially filtered reflected reference beam R42A is shown in Figure 3A to strike over the dispersion detector element 130a. The spatially filtered reflected reference beam R42A is diffracted in the plane of FIG. 3A by the dispersion detector element 130a according to the reflected reference beam R42B. The reflection reference beam R42B strikes the second dispersion detector element 130b. The reflection reference beam R42B is diffracted in the plane of Fig. 3A by the second dispersion detector element 130b along the spatially filtered reflected reference beam R42C filtered by the wave number. Although the beams R42B and R42C are made up of the spectrum of the optical frequency components and the angles are distributed in the plane of Fig. 3A, the path of only one optical frequency component for the beams R42B and R42C is shown in Fig. 3A do. The depicted path is typical. The description of only one optical frequency component for the beams R42B, R42C can be made without worsening the spirit or the meaning of the present invention and without wasting the intricacies of Fig. 3a and the continuation drawing, Allowing the display of important characteristics of the section 84 with respect to the reflective reference beam R42C.

The wave-filtered, spatially filtered reflection reference beam R42C enters the subsystem 84 shown in FIG. The plane of FIG. 31 is perpendicular to the plane of FIG. 3A. In FIG. 31, a wavenumber-filtered, spatially filtered reflection reference beam R42C passes through a lens 66 and is filtered with a wave number comprised of optical beams R42D-1, -2, -3, -4, Lt; RTI ID = 0.0 > R42D < / RTI > The spatially filtered reflected reference beam R42D is filtered with a wavenumber described with only one optical frequency component in Figure 31 and is focused on the lens 66 at the image point 48 in the image plane 47 of interest Loses. The position of the image point 48 in the image plane 47 and thus the position of the image point 48 on the linear array of detector pinholes located in the image plane 47 is filtered with a wavenumber, Dependent on the optical frequency of beam R42D. The light beam portion passing through the linear array of detector pin holes is detected by the detector 114.

The remainder of the third embodiment described in FIGS. 3A-3L is preferably the same as that described for the corresponding embodiment of the first preferred embodiment in the description of FIGS. 1A-1L.

The level 1 discrimination in the third preferred embodiment of the present invention is obtained by adjusting the impulse response function of the subimaging system of the present invention in a plane orthogonal to the plane defined by the dispersion detector elements 130a, 130b. Further, the level 1 type discrimination is obtained in a modification of the third preferred embodiment, in which the apparatus of modification and the electronic processing means are provided with a phase shifter 14, 24, or 34 rotated by? / 2 relative to each optical axis with respect to the third preferred embodiment ). ≪ / RTI > The remainder of the modification of the third embodiment is preferably the same as that described in the description of the modification of the first preferred embodiment of the present invention.

4A-4F, the source subsystem 80a, the subsystem 81b, and the detector subsystem 84a are configured for a first group of implementations that are preferably configured for approximate slit confocal microscopy The fourth embodiment of the present invention will be described in an approximate form. The same reference numerals are used in Figures 4A-4F for the same elements described above with respect to Figures 3A-3L. The variant of the subsystem 80a shown in Figure 4b is now preferably in the region of the source 10a composed of a broadband, spatial incoherent line source, preferably a lamp filament or laser array, Is present in the area of the pinhole 8 of the third embodiment which is now preferably configured as a linear array of source pinholes 8a aligned with the image of the line source 10a. The modification in the subsystem 81b shown in Figures 4c and 4d is configured with a replacement pinhole 18a in the subsystem 81a of the third embodiment with a linear array of spatial filter pinholes 18b in the subsystem 81b do. The variation in subsystem 84a shown in Figures 4e and 4f is that the linear array of pinholes in the image plane 47 of the third embodiment is now preferably a two dimensional array of detector pinholes and a third implementation with a linear array of pixels The exemplary detector 114 now resides in the region of the detector 114a which is preferably a detector 114a comprised of a two-dimensional array of pixels.

In Figure 4b, the linear array of source pinholes 8a and source 10a are aligned perpendicular to the plane of Figure 4b and the plane of Figure 4b is perpendicular to the plane of Figure 4a. In Figures 4c and 4d, the linear array of spatial filter pinholes 18b are aligned perpendicular to the planes of Figures 4c and 4d and the planes of Figures 43c and 4d are perpendicular to the plane of Figure 4a. In Figures 4e, 4f, the two-dimensional array of detector pinholes and the two-dimensional array of detector pixels are aligned perpendicular to the plane of Figures 4e, 4f.

The remainder of the fourth embodiment described in Figures 4A-4F is preferably the same as described for the corresponding aspect of the third preferred embodiment in the description of Figures 3A-3L.

In a fourth preferred embodiment of the present invention, level 1 discrimination is obtained by adjusting the impulse response function of the imaging subsystem of the apparatus of the present invention in a plane orthogonal to the plane defined by the dispersion detector elements 130a, 130b. Further, the level 1 type discrimination is obtained in the first modification of the fourth preferred embodiment, in which the apparatus and the electronic processing means of the first variant are provided with a phase shifter (not shown) which is rotated by? / 2 radians with respect to each optical axis with respect to the fourth preferred embodiment 14, 24, 34). The remainder of the first modification of the fourth embodiment is preferably the same as that described for the corresponding aspect of the first modification of the second preferred embodiment of the present invention.

A second variant of the fourth preferred embodiment is described in which the apparatus of the second variant and the electron processing means comprise a spatial filter pinhole 18a and source pinhole 8a of the fourth preferred embodiment interchanged by the source slit and the spatial filter slit Are substantially the same with respect to the fourth preferred embodiment except for the linear array. The remainder of the second modification of the fourth embodiment is preferably the same as that described for the corresponding aspect of the fourth preferred embodiment of the present invention.

The reduction of the grid effect of the out-of-focus image for the second variant of the fourth preferred embodiment is substantially the same as that obtained in the prior art slit interference microscope. However, although the stabilizing effect due to the out-of-focus image in the second variant of the fourth preferred embodiment is reduced below that obtained in the prior art confocal interference microscope, It is not as effective as that obtained in the apparatus of the first variant.

Using a linear array of source pinholes and a linear array of spatial pinholes, as in the first and fourth preferred embodiments of the fourth preferred embodiment instead of each slit, Creating a need for limited scans of the material. The direction of the limited scan is the direction of the image of the linear array of source pin holes in the material of interest. The limited scan occurs due to the spacing between the pinholes in the direction of the image of the linear array of source pinholes in the material of interest. In addition, the high sensitivity to the spatially filtered, spatially filtered scattering probe beam, which is filtered by the wavenumbering, depends on the condition that the spacing between the pinholes in the direction of the image of the linear array of source pinholes in the material of interest in successive equations (54) .

The number of steps of the limited scan is determined by the ratio of the spacing between each of the imaging subsystem resolution and the image of the two contacting source pin holes in the target material. Indeed, the number of steps of the limited scan would be significantly less than the number of pinholes and spatial filter pinholes in the linear array of source pinholes. Thus, using the apparatus of the first and fourth preferred embodiments of the fourth preferred embodiment together with a linear array of spatial filter pinholes and source pinholes, the two-dimensional representation of the section of material of interest can be obtained substantially without scanning.

It is known from variations of the embodiment and description of the embodiments that the amplitude and phase of the complex amplitude of the scattering probe beam scattered and / or reflected by the material of interest are obtained by each of the five groups of embodiments and variants. Significantly reduced stability errors and reduced systematic errors in determining the complex amplitude of the scattering probe beam for each embodiment and modification are related to the maximum density of data that can be stored and retrieved for a given recording medium of the optical disk And the recording medium is the target material.

The format of the data stored in the memory site is typically binary with one bit useful for use. Can be stored in a given recording medium of the optical disk, with an increased signal-to-noise ratio afforded by the cited characteristics of reduced steady-state error and reduced systematic error for embodiments of the five groups of embodiments described herein, The maximum density of the data can be increased. The data stored in the memory site may be expressed in (base N) x (base M) format, where base N is for an N number of amplitude windows for which the amplitudes of the complex amplitudes are compared, and base M is the phase of the complex amplitude And is for the M number of phase windows compared.

For embodiments of the five groups of embodiments and variations, the amplitudes of the complex amplitudes are processed by a series of N window comparator electronic processors to determine where in the N windows the amplitudes are located. Similarly, the phase of the complex amplitude is processed by a series of M window comparator electronic processors to determine where in the M window the phase is located. The values of N and M that may be used will be determined by factors such as the signal-to-noise ratio obtained and the processing time required. The increase in maximum density of data stored in the optical memory by use of one of the five group embodiments is proportional to the product N x M.

From the second group of embodiments, the presently preferred fifth embodiment of the present invention has many elements from the first group of embodiments to the first embodiment in which the same number performs functional analog to a given element. In the confocal microscopy system shown in FIG. 1A, subsystem 82 is replaced by subsystem 82aa, dispersive elements 130c and 130d, and subsystem 85; To the subsystem 83aa, the mirror 120a, and the subsystem 95, as shown in Figure laa to provide a fifth embodiment of the invention. The fifth embodiment includes a Mickelson interferometer that includes a beam splitter 100, an object material 112, a transillator 116, a reference mirror 120, a dispersion probe beam element 130c, 130d, 130a, and 130b, and a detector 114. [

As shown in FIG. 1A, a light beam P22B consisting of a light beam P22B-1, -2, -3, -4 is partially transmitted by the beam splitter 100 and is transmitted partially to the subsystem 82aa ).

In Fig. 1A, the light beam P22B hits a phase shifter 24 composed of phase shifters 24-1, -2, -3, -4. The plane of Figure 1ab is perpendicular to the plane of Figure laa. The phase shifter 24 is composed of the same number of 2m elements as the phase shifter 14 and is shown as m = 2 in Fig. The light beams P22B-1, -2, -3 and -4 pass through the phase shifters 24-1, -2, -3 and -4, respectively, 4). ≪ / RTI > The phase shifters introduced by the phase shifters 24-1, -2, -3, -4 are the same value, which is larger than the phase shifters introduced by any one of the phase shifters 24-2 and 24-4 by? Radians, 24-2, 24-4) have the same value.

The phase shift produced by each pair of phase shifters 14-1 and 24-1, (14-2 and 24-2), (14-3 and 24-3) and (14-4 and 24-4) Lt; RTI ID = 0.0 > radian. ≪ / RTI > There is no pure relative phase shift between any two of the light beams P22C-1, -2, -3, -4. The light beam P22C is incident on a light beam P22D-1, -2, -3, -4 composed of the light beams P22D-1, -2, -3, -4 focused at the first intermediate probe beam spot at the image point 18 within the in- P22D. ≪ / RTI > The light beam P22D appears from the image point 18 as a light beam P32 composed of the light beams P22-1, -2, -3, -4. The light beam P32 enters a lens 36 having an optical axis aligned with the optical axis 3 subsystem 82aa. The light beam P32 emerges from the lens 36 and exits the subsystem 82aa as a parallel light beam P22A composed of the light beams P22A-1, -2, -3, -4.

In Figure laa, the probe beam P32A strikes the third dispersion element, and the dispersion probe beam element 130c is preferably a transmission diffraction grating. The probe beam P32A is diffracted by the third dispersing element 130c in the plane of Fig. 1Aa as a light beam P32B consisting of the light beams P22B-1, -2, -3, -4, respectively. The probe beam P32B hits on the fourth dispersion element, and the dispersion probe beam element 130d is preferably a transmission diffraction grating. The light beam P32B is diffracted by the fourth dispersion element 130d in the plane of Fig. 1Aa as a probe beam P32C composed of the light beams P32C-1, -2, -3, -4, respectively. Although the probe beams P32B and P32C are composed of the spectrum of the optical frequency components and the angle is diffracted in the plane of Fig. Laa, the path of only one frequency component of the probe beams P32B and P32C is shown in Fig. . The depicted path is typical. The description of only one optical frequency component for the probe beams P32B and P32C can be applied to the probe beam P32C without deviating from the spirit or the meaning of the present invention and without introducing unreasonable complexity into the figures 1aa and continuing figures Lt; RTI ID = 0.0 > 85 < / RTI >

The probe beam P32C is incident on the subsystem 85 to form a probe beam P32D each including the light beams P32D-1, -2, -3, -4 And passes through the lens 46. The probe beam P32D is focused by the lens 46 to illuminate the subject material 112 by forming a line image in the in-focus image plane 27 in the subject material 112. [ The line image of the in-focus image plane 27 includes an image point 28. The axis of the optical image is substantially perpendicular to the optical axis 3a of the image subsystem 85. The line image is determined by a combination of elements such as the focal length of the lens 46 and the scattered probe beam components 130c and 130d, all of which are adjusted, and the optical bandwidth of the source 10. The line sections may be divided along one or more surfaces or placed on the surface of the material of interest. The optical axis of the lens 46 is aligned along the optical axis of the subsystem 85.

1A, the light beam 22A is partially reflected by the beam splitter in accordance with the light beam R22B composed of the light beams R22B-1, -2, -3, -4. As shown in Fig. 1ad, the light beam R22B is incident on the subsystem 83aa. The plane of Fig. 1ad is perpendicular to the plane of Fig. As shown in Fig. 1ad, the light beam R22B hits the phase shifter 34 composed of the phase shifters 34-1, -2, -3, -4. The phase shifter 34 includes elements having the same number of 2m as the phase shifter 14 shown in 1ad with m = 2 and the light beam R22B passes through the phase shifter 34 and passes through the phase shifter 44 And appears as a light beam R22S composed of light beams R22C-1, -2, -3, -4. The phase shift introduced by the phase shifter 44 is controlled by the signal 132 from the computer 118.

The phase shift introduced by the phase shifters 34-1 and 34-3 is the same value as the phase shift introduced by one of the phase shifters 34-2 and 34-4 by a radian larger than the phase shift introduced by the phase shifters 34-2 and 34-4, 2, and 34-4 have the same value. Thus, there is no net phase shift between any two of the light beams R22C-1, -2, -3, -4. The light beam R22C passes through the lens 56 like a light beam R22D composed of light beams R22D-1, -2, -3, -4. The light beam R22D is focused by the lens 56 into the first medium reference beam spot of the image point 38 in the in-focus plane 37. The optical axis of the lens 56 is aligned along the optical axis of the subsystem 83. The reference beam R22D diverges from the medium reference beam spot in the image point 38 along the reference beam R32 consisting of light R22D-1, -2, -3, -4, respectively. The reference beam R32 has an optical axis aligned along the optical axis 3b of the subsystem 83aa. The reference beam R32 emanates from the lens 66 and exits to the subsystem 83aa along the reference beam R32A each composed of the light beams R32A-1, -2, -3, -4.

1aa shows a case where the reference beam is reflected by the mirror 120a and is directed to the subsystem 95 along a reference beam R32B consisting of optical beams R32B-1, -2, -3, Are shown. In FIG. 1A, reference beam R32B is shown passing through lens 76 in accordance with reference beam R32C, which is composed of optical beams R32C-1, -2, -3, -4, respectively. The reference beam R32C is focused by the lens 76 onto the image point 48 of the in-focus image plane 47 on the reference mirror 120. The optical axis of the lens 176 is aligned along the optical axis 3c of the subsystem 95.

In Fig. 1af, a portion of the probe beam P32D (as compared to Fig. 1c) is moved along the scattered probe beam P42 composed of the light beams P42-1, -2, -3, -4, Reflected and / or scattered by the illuminated object material in the line image area in the mask 27. The scattered probe beam P42 emanates from the line image of the in-focus image plane 27 and enters the lens 46. 1F, the scattered probe beam P42 is diffused from the lens 46 to form a scattered probe beam P42A composed of the light beams P42A-1, -2, -3, -4, respectively, And exits the subsystem 85 in parallel.

As shown in FIG. 1A, the scattered probe beam P42A strikes the fourth probe beam component 130d. The portions of the scattered probe beam P42A are scattered by the scattered probe beam component 130d in the plane of FIG. 1Aa, such as a scattered probe beam consisting of light beams P42B-1, -2, -3, Diffracted. The scattered probe beam P42B strikes the third scattered probe beam component 130c. The portions of the scattered probe beam P42B are diffracted in the plane of Fig. 1Aa like the scattered probe beam P42C composed of the light beams P42C-1, -2, -3, -4, respectively. Although the scattered probe beams P42B and P42C are composed of the spectrum of the optical frequency components and are dispersed at the angle of the plane of Fig. 1AA, the path of only one frequency component of the scattered probe beams P42B and P42C is shown in Figs. As shown. The optical frequency of the component paths of the scattered probe beams P42B and P42C is the same as the component path of the probe beams P32B and P32C shown in FIG.

The scattered probe beam P42C shown in Fig. 1ag is incident on the subsystem 82aa (as compared to Fig. Iaa). In Fig. 1ag, the scattered probe beam P42C is incident on the lens 36 and diffused like a scattered probe beam P42D composed of the light beams P42D-1, -2, -3, -4, respectively. The lens 36 aligns the focal point of the scattered probe beam P42D with the intermediate scattered probe beam spot of the image point 18 in the in-focus image plane 17. Although the path of the one-light frequency component of the scattered probe beam P42D is shown in Fig. 1ag, the image point of all the optical frequency components of the scattered probe beam P42D is the same as schematically shown in Fig. 1ag ; An optical system consisting of a lens 36, scattered probe beam components 130c and 130d, a lens 46 and an object material 112 is conjugated to the entire spectrum of the optical frequency components of the beam P32, Is a confocal imaging system that is an image point.

1AG, the scattered probe beam P42D is diffused from the image point 18 like the scattered probe beam P52 composed of the light beams P52-1, -2, -3, -4, respectively. The scattered probe beam P52 is incident on the lens 26 and becomes parallel to form a scattered probe beam P52A composed of the light beams P52-1, -2, -3, -4, respectively. The light beams P52A-1, -2, -3, -4 pass through the phase shifters 24-4, -3, -2, -1, respectively, and pass through the light beams P52B0-1, , 4). The light beams P32B-1, -2, -3, -4 constitute a scattered probe beam P52B exiting the subsystem 82aa. The phase shift introduced by the phase shifters 24-1 and 24-3 is equal to a value that is larger than the phase shift introduced by one of the phase shifters 24-2 and 24-4 by a radian, 2, and 24-4 have the same value.

In FIG. 1 (a), reference beam R32D (compared with FIG. 1A) is mirrored by mirror 120, such as a reflected reference beam R42 comprised of optical beams R42-1, Reflection. The reflected reference beam R42 emanates from the image point 48 in the in-focus plane 47 and enters the lens 76. As shown in Fig. 1 (a), the reflected reference beam R42 is incident on the lens 76 in parallel with the reflected reference beam R42A composed of the light beams R42A-1, -2, -3, -4, .

1A, the reflected reference beam R42A is reflected by the mirror 120a and is reflected by the subsystem 83aa, such as a reflected reference beam R42B composed of light beams R42-1, -2, -3, ). In Fig. 1ai, the reflected reference beam R42B passes through the lens 66 like a reflected reference beam R42C composed of light beams R42C-1, -2, -3, -4, respectively. The reflected reference beam R42C is focused by the lens 66 into the intermediate reflected reference beam image spot of the image point 38 of the in-focus image plane 37. The reference beam R42C is diffused from the intermediate reflected reference beam spot at the image point 38 like the reference beam R52 composed of the light beams R52-1, -2, -3, -4, respectively. The reference beam R52 is incident on the lens 56 and diffused from the lens 56 like the reference beam R52A composed of the light beams R52A-1, -2, -3, -4, respectively. As shown in Fig. 1ai, the reflected reference beam R52 diffuses from the lens 56 like a parallel reference beam R52A composed of light beams R52A-1, -2, -3, -4, respectively . The light beams R52A-1, -2, -3, -4 are first transmitted to the phase shifter 44 in order to spread like the reference beam R52B composed of the light beams R52B-1, -2, -3, And passes through each of the phase shifters 34-4, -3, -2, -1. The phase shift introduced by the phase shifter 44 is controlled by the signal 132 from the computer 118. The phase shift introduced by the phase shifters 34-1 and 34-3 is the same value as the phase shift introduced by one of the phase shifters 34-2 and 34-4 by a radian larger than the phase shift introduced by the phase shifters 34-2 and 34-4, 2, and 34-4 have the same value. The light beams R32B-1, -2, -3, -4 including the light beam R32B exit the subsystem 83aa.

The remaining description of the fifth embodiment of the present invention is the same as the corresponding portion of the specification given in the first embodiment.

The interference cross between the complex amplitude of the wavenumber filtered and spatially filtered scattered probe beam P42D of the first embodiment and the complex amplitude of the spatially filtered reflected reference beam R42D filtered by the wave number, The interference cross-term between the complex amplitude of the wavenumber-filtered and spatially filtered scattered probe beam P62D and the spatially filtered reflected reference beam R62D filtered by the wavenumbers of the five exemplary embodiments, And the respective sections are obtained at the same time. In the first embodiment, the orthogonal lines of the object material 112 are substantially parallel to the optical axis 3 of the subsystem 82, and in the fifth embodiment, the line sections in the object material 112 are aligned with the subsystem 85 And is substantially orthogonal to the optical axis 3a.

In a fifth preferred embodiment of the present invention, the level 1 demarcation is defined by the device of the present invention in a plane perpendicular to the plane defined by the dispersive probe beam components 130c, 130b and the dispersive detector components 130a, By adjusting the impulse response function of the imaging subsystem of FIG. The level 1 type division is characterized in that the device and the electronic processing means of the modification substantially identical to the fifth preferred embodiment with the phase shifters 14, 24 and 34 rotated by? / 2 radians for each optical axis are substantially the fifth preferred embodiment Can be obtained through a modification of the fifth preferred embodiment like the embodiment. The reduction of the structural effect of the out-of-focus image of the variant of the fifth preferred embodiment is the same as the fifth preferred embodiment. The statistical effect due to the out-of-focus image of the variant of the fifth preferred embodiment is reduced to that which is obtained in the confocal interference microscope of the prior art, but is not generally the same as that obtained with the apparatus of the fifth preferred embodiment.

The sixth preferred embodiment of the present invention from the second group of embodiments comprises a plurality of components which function similarly to the same number of components of the first to the second embodiment from the first group of embodiments, It is fitted to an approximate slit-shaped confocal microscope. In the confocal microscopy system shown in FIG. 2A, subsystem 82 is replaced by subsystem 82aa, distributed components 130c and 130d, and subsystem 85; The subsystem 83 is then replaced by a subsystem 83aa, a mirror 120a, and a subsystem 95, as shown in Figure 2aa, to provide a sixth preferred embodiment of the present invention. The sixth embodiment includes a beam splitter 100, an object material 112, a translators 116, a reference mirror 120, scattered probe beam components 130c and 130d, scattered detector components 130a, 130b, and a detector 114a.

The remaining description of the sixth embodiment is the same as the corresponding portion of the given specification of the second and fifth embodiments.

The interference cross between the complex amplitude of the wavenumber filtered and spatially filtered scattered probe P42D of the second embodiment and the complex amplitude of the spatially filtered reflected reference beam R42D filtered by the wavenumbers, The complex amplitude of the filtered and spatially filtered reflected reference beam R62D, filtered by the complex amplitude and wave number of the wavenumber filtered and spatially filtered scattered probe beam P62D of Example 6, is applied to a substantially orthogonal two-dimensional section of the material of interest And the image points of each two-dimensional surface are obtained at the same time. In the second embodiment, the normal of the two-dimensional section of the object material 112 is substantially orthogonal to the optical axis 3 of the subsystem 82, and in the sixth embodiment, the normal of the two- The normal is substantially orthogonal to the optical axis 3a of the subsystem 85.

A seventh preferred embodiment of the present invention from an embodiment of the seventh group comprises a plurality of components which function similar to the same number of elements from the first group of embodiments to the third embodiment. In the confocal microscopy system shown in FIG. 3A, the subsystem 82 is replaced by a subsystem 82aa, distributed components 130c and 130d, and a subsystem 85; The subsystem 83a is then replaced by a subsystem 83ab, a mirror 120a, and a subsystem 95, as shown in Figure 3aa, to provide a seventh preferred embodiment of the present invention. The seventh embodiment includes a beam splitter 100, an object material 112, a translators 116, a reference mirror 120, scattered probe beam components 130c and 130d, scattered detector components 130a, 130b, and a detector 114a.

The remaining description of the seventh embodiment is the same as the corresponding part of the given specification of the third and sixth embodiments.

The interference cross between the complex amplitude of the wavenumber filtered and spatially filtered scattered probe P42D of the third embodiment and the complex amplitude of the spatially filtered reflected reference beam R42D filtered by the wave number, The complex amplitude of the filtered and spatially filtered reflected reference beam R62D filtered by the complex amplitude and wave number of the wavenumber filtered and spatially filtered scattered probe beam P62D of Example 7 corresponds to the two substantially orthogonal line sections And the image points of each of the line sections are obtained at the same time. In the third embodiment, the subject material 112 is substantially parallel to the optical axis 3 of the subsystem 82 of the seventh embodiment, and in the seventh embodiment, the line section of the subject material 112 is sub- 85 substantially orthogonal to the optical axis 3a.

The eighth preferred embodiment of the present invention from the second group of embodiments comprises a number of components which function similar to the same numbered components of the fourth embodiment from the first group of embodiments. In the confocal microscopy system shown in FIG. 4A, subsystem 82 is replaced by subsystem 82aa, distributed components 130c and 130d, and subsystem 85; The subsystem 83a is then replaced by a subsystem 83ab, a mirror 120a, and a subsystem 95, as shown in Figure 4aa, to provide an eighth preferred embodiment of the present invention. The eighth embodiment includes a beam splitter 100, an object material 112, a translators 116, a reference mirror 120, scattered probe beam components 130c and 130d, scattered detector components 130a, 130b, and a detector 114a.

The remaining description of the eighth embodiment is the same as the corresponding part of the given specification of the fourth and seventh embodiments.

The interference cross between the complex amplitude of the wavenumber filtered and spatially filtered scattered probe P42D of the fourth embodiment and the complex amplitude of the spatially filtered reflected reference beam R42D filtered by the wave number, The complex amplitude of the filtered and spatially filtered reflected reference beam R62D, filtered by the complex amplitude and frequency of the wavenumber filtered and spatially filtered scattered probe beam P62D of Example 7, corresponds to two substantially orthogonal two-dimensional Section, and the image points of each of the two-dimensional sections are obtained simultaneously. In the fourth embodiment, the normal of the two-dimensional section of the object material 112 is substantially orthogonal to the optical axis 3 of the subsystem 82 and, in the eighth embodiment, The normal is substantially orthogonal to the optical axis 3a of the subsystem 85.

Modifications of the ninth, tenth, seventh and twelfth embodiments of the present invention and the third group of embodiments are the same as those of the first embodiment except that the phase shifters 14, 24, 34 and 34a are omitted, 1, the second, third and fourth embodiments, and variations of the same. In the third group of embodiments, the remainder of the embodiments of the invention and the modifications of the variants are identical to the embodiments of the invention from the first group of embodiments except for the level of statistical accuracy of obtaining an image at a given time interval ≪ / RTI > is the same as the corresponding part of the specification given in the example and variant.

Embodiments of the present invention and the level of statistical accuracy at which images are acquired at predetermined time intervals of a variant are obtained from embodiments of the third group and statistical methods for obtaining images at predetermined time intervals with embodiments of the present invention It is superior to the level of accuracy. However, the statistical error introduced by the amplitude of the out-of-focus image is less than the corresponding statistical error introduced as the amplitude of the out-of-focus image in the prior art confocal interferometer microscopy. The embodiments of the third group of embodiments and the apparatus of the variants.

The magnitude of the interference cross-term between the complex amplitude of the wave-filtered and spatially filtered background beam and the complex amplitude of the spatially filtered reflected reference beam filtered with the wave number in the detector image plane of the embodiment is compared with the pixel- Will be substantially the same as those obtained in the corresponding interference cross term in the confocal interference microscope of Fig. However, at certain time intervals, the statistical errors for each image point of the imaged line section of the material of interest obtained with the embodiment of the third group of embodiments and the apparatus of the variant thereof are compared with those of prior art confocal interferometer microscopy At a single image point of, and at the same time interval. A similar description applies in comparison to the imaging of a two-dimensional section of the material of interest. This difference is due to the statistical error introduced as the amplitude of the out-of-focus image, considering the statistical accuracy of the image of the line section or two-dimensional section of the material of interest obtained at the same time interval, Based image is much more reduced in embodiments of the third group of embodiments and variants thereof as compared to the corresponding statistical errors introduced by the out-of-focus image of the micro-scopes.

Preferred embodiments (13, 14, 15, 16) and variants thereof of the present invention from the fourth group of embodiments are identical to the embodiments of the present invention except that the phase shifters 14, 24, 34, Fifth, sixth, seventh, eighth embodiment and its variants. Embodiments of the fourth group of embodiments and the remainder of the variants thereof are the same as those of the embodiment from the seventh group of embodiments except for the reduction of the background from the out-of-focus image and the level of correction, It is the same as the corresponding part of the given specification.

The background reduction and correction level from the out-of-focus image obtained from the embodiment of the second group to the embodiment and its variants is similar to the embodiment from the fourth group of embodiments and the out- Is higher than the level of reduction and correction of the background from the orbital image. However, the statistical error introduced by the amplitude of the out-of-focus image will be much less than the corresponding statistical error introduced by the amplitude of the out-of-focus image of the prior art confocal interferometer microscope . The complex amplitude of the spatially filtered and spatially filtered background beam and the complex amplitude of the filtered and spatially filtered reflected reference beam in the detector image plane of the embodiment of the fourth group of embodiments and its variants The magnitude of the interference cross term between them will be substantially the same as compared to those obtained in the corresponding interference cross term of the prior art confocal interferometer microscope pixel by pixel. However, at certain time intervals, the statistical errors per image point of the imaged line section of the object material obtained with the embodiment of the fourth group of embodiments and the apparatus of its variants are less than those of prior art confocal interferometer microscopes At a single image point, and at the same time interval, it is substantially statistically the same as that obtained. A similar description applies in comparison to the imaging of a two-dimensional section of the material of interest. This difference is due to the statistical error introduced by the amplitude of the out-of-focus image, considering the statistical accuracy of the image of the line section or two-dimensional section of the material of interest obtained at the same time interval, Based on the determination that the corresponding statistical error introduced by the out-of-focus image of the micro-scopes will be much more reduced in the embodiment of the fourth group of embodiments and its variants.

Preferred embodiments (17, 18, 19, 20) and variants thereof of the present invention from the fifth group of embodiments replace the non-chromatic probe lenses of the first group of embodiments and their modifications with the probable probe lenses And the same components and subsystems as those of the first, second, third, fourth embodiment and its variants. The embodiment of the fifth group of embodiments and the remainder of the variants thereof are the same as the embodiment from the first group of embodiments and the correspondence of the specification given to the variant, except for the level of statistical accuracy obtained in the given time interval .

The reduction of the background and the level of correction from the out-of-focus image obtained from the embodiment of the fifth group to the embodiment and its variants is achieved by the embodiment from the first group of embodiments and the out- Is equal to the level of reduction and correction of the background from the orbital image. However, the statistical error introduced by the amplitude of the out-of-focus image is less than the corresponding statistical error introduced by the amplitude of the out-of-focus image into the embodiment of the fifth group of embodiments In the embodiment of the group of embodiments and the apparatus of its variants, the better and the fifth group of embodiments acquire image points in succession in time.

The reduction of the background from the out-of-focus image and the level of correction, obtained from the embodiment of the fifth group and the variants thereof, are the out-of-focus images obtained with the prior art confocal interferometer microscopes Lt; RTI ID = 0.0 > and / or < / RTI > The complex amplitude of the spatially filtered and spatially filtered background beam and the complex amplitude of the filtered and spatially filtered reflected reference beam in the detector image plane of the embodiment of the fifth group of embodiments and its variants The magnitude of the interference cross term between them will be substantially the same as compared to those obtained in the corresponding interference cross term of the prior art confocal interferometer microscope pixel by pixel. Thus, the statistical accuracy and the level of hierarchical error in obtaining images with embodiments from the fifth group of embodiments and variants thereof in a given time interval may be the same with the prior art confocal interferometer microscopes Which is better than the level of statistical errors and hierarchical errors in obtaining images at time intervals.

Those skilled in the art will appreciate that phase shifters 14, 24, 34, and 34a may be used to change the characteristics of the present invention with respect to the degree of signal degradation and spatial resolution from out-of-focus images without departing from the spirit and scope of the present invention. As shown in FIG. It will also be understood by those skilled in the art that the function of the phase shifters 14, 24, 34, 34a can be performed by a combination of other phase shifters without departing from the spirit and scope of the present invention or of a concentric annuli or a section of a geometric pattern Components of the present invention.

The phase shifters 14, 24, 34, 34a, 44 may be of the electrooptical type or of the dispersive optical component type. The criteria for the type of dispersive optical component are given in the paragraph on broadband operation below. Alternatively, the phase shift described as being introduced by phase shifter 44 may alternatively be generated by rearranging a mirror, such as reference mirror 120, for example, normal to the mirror's reflective surface.

When the phase shifts generated by the phase shifters 14, 24, 34, 34a and 44 are not wavelength dependent, an improved performance of the inventive arrangement of a broadband source is obtained. The phase shifters 14, 24, 34, 34a and 44 are represented by HAHill, JW Figoski and PTBallard, US Pat. No. 4,213,706 ('80 .7), "Background Compensating Interferometer," and HAHill, JW Figoski and PTBallard Quot; Background Compensating Interferometer ", U.S. Patent No. 4,304,446 ('81. 12), the requirements of a broadband phase shifter can be met.

Each embodiment of the five group of embodiments and its variants has a corresponding embodiment or variant comprising a recording medium for recording information of the material of interest. Each embodiment and variant for recording information includes the corresponding embodiments of the fifth group of embodiments and the method and apparatus of the variant, except for the following configuration changes; The source and reference mirror subsystems are interchanged and the detector and detector pinholes are relocated to a recording mirror oriented to light from a source that substantially hits the back surface of the recording mirror. The reflectivity of the write mirror and the phase shift introduced by the write mirror serve to position on the write mirror aligned with respect to the phase shift product to produce the desired image on the target material. The phase shifting product is a wavenumber filtered and spatially filtered reflected reference beam to obtain values of the first, second, third and fourth measured intensities in the embodiment of the fifth group of embodiments and its variants Performs a similar function to the product that introduced the sequence of phase shifts.

In an embodiment of the above-described recording, the recording process includes a number of different mechanisms and the recording medium, which is an optical disc, comprises a multiplicity of different materials and a mixture of different materials. Embodiments of the recording process include electrophotographic and magneto-optical effects such as Faraday rotation and Kerr effect as well as photochemical hole burning.

When the magneto-optic effect is used in the recording process and the stored information is retrieved by detecting a change in the polarization state of the scattered or transmitted probe beam, the embodiment of the fifth group of embodiments differs from the complex amplitude of the scattered probe beam And is configured to detect the polarization of the probe beam. The fifth group of embodiments is configured to measure the scattering of the scattered probe beam by passing the scattered probe beam through an analyzer such as a polarizing beam splitter and measuring the complex amplitude of the polarized state of the scattered probe beam separated by the analyzer .

The amplitude recording medium, the nonlinear amplitude recording recording medium and / or the phase recording medium may be used in combination with an embodiment of the described recording, reduced statistical errors and reduced hierarchical errors associated with images in the recording medium, When used together, the density of the data stored in the memory site is proportional to N x M, where N and M are the same as those used in the description of the readout embodiment, which is the fifth group embodiment.

The information content stored at a given memory site is controlled by the spatial distribution of the reflected power and the spatial distribution of the phase shift generated by the recording mirror of the recording embodiment and its variants. The windowed reflectivity and windowed phase shifts caused by the write mirror are controlled by the metrics of the electrooptic amplitude modulator and the phase shifter located at the front of the mirror and the electrooptic amplitude modulator and phase shifter are connected to the computer The windowing of the reflected power and the phase shift is similar to that used for windowing the amplitude and phase of the measured complex scattering amplitude of the fifth group of embodiments.

A spatially filtered and wavenely filtered scattered probe beam and a spatially filtered and wavenhed filtered reference beam measured by embodiments and variants of the first and third group of embodiments of the axial direction of the probe lens The interference term is proportional to the Fourier transform of the complex scattering amplitude at the image site of the material of interest. Similarly, by recording embodiments and variants corresponding to embodiments and variants of the first and third groups of embodiments, the information stored in the memory site is stored in a corresponding spatially filtered and wavenely filtered, mirrored Is proportional to the reflected reference beam spatially filtered with the filtered beam and filtered by the wavenumbered beam and is proportional to the Fourier transform of the complex reflection power of each site of the recording mirror.

One of ordinary skill in the art will recognize that the interference term between the spatially filtered and wasted filtered beam reflected by the recording mirror and the spatially filtered and wasted filtered reference beam is proportional to the inverse Fourier transform of the information stored at the memory site, When the complex reflection power of the mirror is determined, the spatially filtered and wavenely filtered scattered probe beam measured spe- cifically by the embodiment and variations of the first and third group embodiments in the axial direction of the probe beam, The measured interference terms between the filtered reference beams filtered by the filter are proportional to the stored original information. Thus, in this embodiment, it is necessary to perform the axial Fourier transform of the complex scattering amplitude measured by the embodiments of the first and third groups of embodiments and the modifications to recover the stored original information none.

One advantage of any of the embodiments of the first and third groups is that the tomographic composite amplitude images of the wafers used in integrated circuit fabrication are significantly better than those obtained with the single pinhole confocal interference microscopy or holographic measurement sequence of the prior art Is accomplished by simultaneous imaging of line sections in the depth direction to or from the wafer surface, either as a background from reduced or identical statistical errors and significantly reduced unfocused images. Simultaneous imaging of the line section in or out of the wafer surface or in the depth direction of the wafer can be used to significantly reduce the reactivity to wafer motion caused by translation, scanning and / or vibration of the wafer. Simultaneous imaging of the line section in the depth direction of the wafer at or within the surface of the wafer can additionally be used to identify the surface and inner surface of the wafer with information simultaneously obtained at multiple depths.

One of the advantages of any of the first and third group embodiments is that the tomographic complex amplitude image of the wafer used in integrated circuit fabrication is obtained with a single pinhole and slit confocal interference microscopy or holographic measurement sequence of the prior art Is substantially completed by substantially simultaneous imaging of the wafer depth direction line sections, with significantly reduced or the same statistical errors and a background from a significantly reduced out-of-focus image. The one axis of the two-dimensional section of the wafer is parallel to the longitudinal direction of the wafer. Simultaneous imaging of a two-dimensional section of a wafer can be used to drastically reduce the depth of the wafer caused by the translation, scanning and / or vibration of the wafer and the reactivity to lateral movement of the wafer. Simultaneous imaging of a two-dimensional section in a wafer can additionally be used to identify a surface and an inner surface of the wafer with the information simultaneously obtained at other locations, and the surface and / or inner surface can support display purposes.

One advantage of the first and third group of embodiments is that the tomograpy complex amplitude image of the biological specimen in vivo conditions is significantly reduced or equal to that obtained with the single pinhole confocal interference microscopy or holographic measurement sequence of the prior art Can be completed by virtually simultaneous imaging of a line section in the depth direction of the biological specimen, with statistical errors and a background from a significantly reduced out-of-focus image, which image can be obtained, for example, Can be used for biopsy. Simultaneous imaging of the line sections in the depth direction of the biological specimen can be used, for example, to significantly reduce the reactivity to depth and transverse biological specimen motion caused by translation, scanning and / or vibration of the biological specimen . Simultaneous imaging of the line sections in the depth direction of the biological specimen can additionally be used to identify the surface of the biological specimen with information obtained simultaneously at multiple depths.

An advantage of either of the first and third group embodiments is that the tomographic complex amplitude image of the biological specimen in vivo is better than that obtained with a single pinhole and slit confocal interference microscopy or holographic measurement sequence of the prior art Can be completed by substantially simultaneous imaging of a two-dimensional section of a biological sample, with significantly reduced or the same statistical error and a background from a significantly reduced out-of-focus image, said image being, for example, - Can be used for penetration biopsy. Simultaneous imaging of a two-dimensional section of a wafer can be used, for example, to drastically reduce reactivity to depth and transverse biological specimen motion caused by translational motion, scanning and / or vibration of a biological specimen. Simultaneous imaging of the line sections in the depth direction of the biological specimen can additionally be used to identify the surface or inner surface of the biological specimen with information simultaneously obtained at multiple depths, and the surface and / have.

One of the advantages of the embodiments of the second and fourth groups is that the tomographic complex amplitude images of the wafers used in integrated circuit fabrication are significantly better than those obtained with the single pinhole confocal interference microscopy or holographic measurement sequence of the prior art Is accomplished by simultaneous imaging of the line section contacts to or from the wafer surface, with reduced or identical statistical errors and a background from a significantly reduced out-of-focus image. Simultaneous imaging of a line section contact to or from a wafer surface can be used to significantly reduce reactivity to wafer motion caused by translation, scanning, and / or vibration of the wafer. Simultaneous imaging of the two-dimensional section contacts in the wafer or on the surface of the image can additionally be used to identify the surface and the inner surface of the wafer with the information simultaneously obtained at the location, and the reference position can support the display purpose.

An advantage of either of the second and fourth group embodiments is that the tomographed complex amplitude image of the biological specimen in vivo conditions is significantly reduced compared to that obtained with the single pinhole confocal interference microscopy or holographic measurement sequence of the prior art Or can be completed by virtually simultaneous imaging of the line section tangent of the sample, with the same statistical error and as a background from a significantly reduced out-of-focus image, the image being, for example, It can be used for inspection. Simultaneous imaging of a line section to or from a wafer surface can be used to greatly reduce the reactivity to sample motion caused by translational motion, scanning, and / or vibration of the specimen. Simultaneous imaging of a two-dimensional line section tangent to or on a sample may be further used to identify a reference location of the sample with information obtained simultaneously at various locations, and the reference location may support the display purpose.

An advantage of the embodiment of the fifth group is that the tomographed complex amplitude image of the wafer used in the manufacture of the integrated circuit is significantly reduced out-of-the-box compared to that obtained with the sequence measured with single pinhole confocal interference microscopy or holography of the prior art - One-dimensional, two-dimensional or three-dimensional images of wafers are generated with the focus background.

An advantage of the fifth group of embodiments is that tomographed complex amplitude images of biological specimens in vivo can be obtained from out-of-focus images that are significantly reduced from those obtained with the single pinhole confocal interference microscopy or holographic measurement sequence of the prior art Dimensional, two-dimensional or three-dimensional image of the specimen is generated, and the image can be used, for example, for non-penetrating biopsy of a biological specimen.

The confocal interference microscopy system described above can be used in steppers or scanners of lithographic applications used in the manufacture of large scale integrated circuits, such as computer chips, especially in alignment mark identification and in stand-alone metrology systems for measuring the performance of a stepper or scanner . The confocal microscopes described above can also be used to inspect masks used in steppers and scanners and to inspect wafers at each stage of large scale integrated circuit fabrication. Lithography is a key technology driver in the semiconductor manufacturing industry.

Improving overlay is one of five difficult attempts to reduce line widths (design rules) to less than 100 nm. See, for example, the Semiconductor Industry Roadmap, p. The economic value of improving the performance of lithography tools is significant, as lithography tools can be produced in the order of five to ten billion dollars a year. Each 1% increase (decrease) in lithography productivity results in an economic benefit (loss) of approximately $ 1 million per year for the integrated circuit manufacturer and results in a substantial comparison benefit or disadvantage to the lithography tool vendor.

The overlay is measured by printing a one-level pattern of wafers and a second pattern of a series of levels of wafers and measuring the distortion of the stand-alone metrology system, position differences, orientation and both patterns.

The stand-alone metrology system includes a microscope system, such as the confocal interference microscopy system described above, connected to a laser gauge-controlled stage to measure the relative position of the pattern and the wafer handling system to see the pattern.

The function of the lithography tool is to transfer spatially patterned radiation onto a wafer coated with a photoresist. This process involves determining the position of the wafer that receives the radiation (alignment), and applying radiation to the photoresist at that location.

To properly position the wafer, the wafer includes alignment marks on the wafer that can be measured by a dedicated sensor, such as the confocal interference microscopy system described above. The measurement position of the alignment mark defines the position of the wafer in the tool. This information, along with the specification of the desired patterning of the wafer surface, indicates the alignment of the wafer with respect to the spatially patterned radiation. Based on this information, the translational stage capable of supporting the photoresist coated wafer moves the wafer so that the radiation exposes the correct position of the wafer.

During exposure, the radiation source illuminates a patterned reticle that scatters the radiation to produce spatially patterned radiation. The reticle is also referred to as a mask, and these terms are used interchangeably below. In the case of reduced lithography, the collimating lens collects the scattered radiation and forms a reduced image of the reticle pattern. Alternatively, in the case of proximity printing, the scattered radiation propagates a small distance (typically on the order of microns) before touching the wafer, producing a 1: 1 image of the reticle pattern. The radiation initiates a photochemical process of the resist that converts the radiation pattern into a latent image in the resist.

When a mask is created, the mask must be made completely. A defect in the pattern will destroy the functionality of the semiconductor circuit printed with the mask. The mask passes through an automated mask inspection system that examines any defects in the pattern before it is delivered to the semiconductor manufacturing line. There are two possible methods for mask overhaul, die-to-database and die-to-die overhaul. The first method includes an automated scanning microscope that directly compares the mask pattern with the computer data used to generate the mask. This requires a very large data processing capacity which is the same as that required by the mask writer itself. Any discrepancy between the overhauled mask pattern and the data set used to create the mask pattern is flagged as an error. The confocal interference microscopy system is particularly suitable for automated mask overhaul because it has the benefit of background reduction and spatial simultaneous acquisition of one-dimensional line section images and two-dimensional section images.

In general, a lithography system is also referred to as an exposure system, and typically includes an illumination system, and a wafer positioning system. The illumination system includes a radiation source that provides radiation such as ultraviolet light, visible light, x-rays, electrons or ion radiation, and a mask or reticle that transfers the pattern to radiation, thereby producing spatially patterned radiation. Additionally, in the case of reduced lithography, the illumination system includes a lens assembly that images the spatially patterned radiation onto the wafer. The imaged radiation exposes the resist coated on the wafer. The illumination system also includes a mask stage that supports the mask, and a position determination system that adjusts the position of the mask stage relative to the radiation transmitted through the mask. The wafer positioning system includes a wafer stage that supports the wafer, and a positioning system that adjusts the position of the wafer stage in relation to the imaged radiation. The fabrication of the integrated circuit may include multiple exposure steps. For a general reference on lithography, see, for example, the references Microlithography : Science and Technology (Marcel Dekker, Inc., New York, 1998) by JR Sheats and BW Smith.

An embodiment of a lithographic scanner 800 using a confocal interference microscopy system (not shown) is shown in Figure 8A. A confocal interference microscopy system is used to accurately position alignment marks on a wafer (not shown) within the exposure system. Here, the stage 822 is used to support and position the wafer with respect to the exposure station. The scanner 800 includes other supporting structures and a frame 802 carrying various components carried on these structures. The exposure base 804 is mounted to the top of the lens housing 806 at the top mounting the reticle or mask stage 816 used to support the reticle or mask. The positioning system for positioning the mask with respect to the exposure station is structurally represented by element 817. [ Positioning system 817 includes, for example, a piezoelectric transducer element and a corresponding control electronics. Although not included in the preferred embodiments described herein, one or more interferometric systems may be used to accurately measure the positioning of the mask stage and other movable elements where the positioning is accurately monitored in the process of manufacturing the lithography structure (See Microwithography in Supra Sheats and Smith : Science and Technology ).

The exposure base 804 suspended below is a support base 813 that carries the wafer stage 822. The stage 822 includes a plane mirror 828 that reflects the measurement beam 854 transmitted by the interferometer system 826 to the stage. The positioning system for positioning stage 822 with respect to interferometer system 826 is structurally indicated by component 819. [ Positioning system 819 includes, for example, a piezoelectric transducer element and a corresponding control electronics. The measurement beam is reflected back onto the interferometer system mounted on the exposure base 804.

During operation, the radiation beam 810 passes through a beam shaping optical assembly 812, for example, an ultraviolet (UV) beam from a UV laser (not shown), reflected from the mirror 814, do. The radiation beam then passes through a mask (not shown) carried by the mask stage 816. A mask (not shown) is imaged onto the wafer on the wafer stage 822 through the lens assembly 808 carried in the lens housing 806. The base 804 and the various components supported by the base are protected from environmental changes by the damping system depicted by the spring 820.

As is known in the art, lithography is a critical component of the manufacturing method of making semiconductor devices. For example, U.S. Patent No. 5,483,343 discloses steps for such a manufacturing method. These steps are described below with reference to Figures 8b and 8c. 8B is a flowchart of a sequence of manufacturing a semiconductor device such as a semiconductor chip (e.g., IC or LSI), a liquid crystal panel, or a CCD. Step 851 is a design process for designing a circuit of the semiconductor device. Step 852 is a process for manufacturing a mask based on circuit pattern design. Step 853 is a process for manufacturing a wafer using a material such as silicon.

Step 854 is a wafer process in which a circuit is formed on a wafer through lithography by using the mask and wafer thus produced, and is referred to as a pre-process. Interferometer positioning of the lithography tool associated with the wafer is required to have a sufficient spatial resolution to form a circuit on the wafer corresponding to these patterns on the mask. The confocal interference microscopy method and system described herein is particularly useful for observing the surface of a wafer and the inner layer is created on the wafer by a wafer process to monitor and inspect the efficiency of the lithography used in the wafer process do. Step 855 is an assembly step called pre-process, and the wafer processed by step 854 is formed of a semiconductor chip. These steps include assembly steps (dicing and bonding) and packaging steps (chip sealing). Step 856 is an inspecting step, and an operability check, a persistence check, and the like of the semiconductor device produced by step 855 are performed. Along with these processes, the semiconductor devices are completed and they are transported (step 857).

8C is a flow chart showing a detailed wafer process. Step 861 is an oxidation process for oxidizing the surface of the wafer. Step 862 is a CVD process for forming an insulating film on the wafer surface. Step 863 is an electrode forming step of forming an electrode on the wafer by vapor deposition. Step 864 is an ion implantation process for implanting ions into the wafer. Step 865 is a resist process for applying a resist (photosensitive material) to a wafer. Step 866 is an exposure process for printing a circuit pattern of the mask on the wafer through the exposure apparatus by exposure (i.e., lithography). Again, as discussed above, the use of confocal interference microscopy systems and methods described herein has improved in accuracy, resolution, and persistence of these lithography steps.

Step 867 is a developing process for developing the exposed wafer. Step 868 is an etching process to remove portions other than the developed resist image. Step 869 is a resist separation step for separating the resist material remaining on the wafer after the etching process is performed. By repeating these processes, a circuit pattern is formed and double-printed on the wafer.

An important application of the confocal interference microscopy method and system is the inspection of the mask and reticle used in the lithographic method. For example, the structure of the mask inspection system 900 is shown in FIG. The source 910 generates a source beam 912 and the confocal interference microscopy assembly 914 transfers the radiation beam to the substrate 916 supported by the movable stage 918. The interferometer system 920 directs the reference beam 922 to the mirror 924 mounted on the beam focusing assembly 914 and the measurement beam 926 to the stage 918. In order to determine the relative position of the stage, To the mirror 928 mounted on the mirror 928. The change in position measured by the interferometer system corresponds to a change in the relative position of the recording beam 912 on the substrate 916. [ The interferometer system 920 sends the measurement signal 932 to the controller 930 which indicates the relative position of the inspection beam 912 on the substrate 916. The controller 930 transmits the output signal 934 to the base 936 that supports and positions the stage 918. [

The controller 930 allows the confocal interference microscopy assembly 914 to scan the inspection beam over the area of the substrate, for example, using signal 944. [ As a result, the controller 930 directs other components of the system to inspect the substrate. The mask check directly compares the mask pattern with the computer data used to generate the mask.

theory

Background discrimination

The apparatus described in all preferred embodiments includes forming a portion of a pinhole or slit confocal interference microscopy system. Background discrimination power of a confocal microscopy system is one of the most important advantages and arises from the strong optical sectioning characteristics of confocal microscopes. This is a completely different nature from the limited depth of the general microscopic field and this difference is that the conventional microscope is somewhat blurred out-of-focus information, whereas in the confocal system information is detected more or less strongly, The light scattered at some locations that are separated by the beam spot is focussed at the detector plane and thus fails to pass efficiently through the mask located there. (See C.J. Sheppard and C. J. Cogswell, " Three-Dimensional Imaging in Confocal Microscopy ", Confocal Microscopy Edited by T. Wilson (Academy Class, London) pp. 143-169 (1990)). For example, the Fizeau interferometer used in DIP has the sensitivity of an out-of-focus image comparable to that found in conventional microscopes.

The characteristics of the confocal interference microsque of the various variations and embodiments of the first, second, and fifth group of embodiments are such that the reflected reference beam and the scattered probe beam are reflected at the in-focus image point 48 The portion of the out-of-focus beam at the in-focus image point 48 is substantially unchanged. For the cited examples and variants of the embodiments, the features of the present invention are used to obtain a reduced out-of-focus image sensitivity compared to that obtained in prior art confocal interference microscopes.

The apparatus described in this embodiment and variations in the embodiments of the first, second, third and fifth groups further include a scheme of a dispersion interferometer. The method of Optical Time Domain Reflectometry (OTDR) consists of scanning light of a short steel pulse onto a subject such as a fiber, and measuring the time-dependent backscattered optical signal. The method of the optical frequency domain reflectometer (OFDR) consists of illuminating the object with monochromatic radiation whose frequency varies with time in a known manner, and measuring the time-dependent backscattered optical signal. In the cited embodiment and its various modifications, the waveness-dependent backscattered optical signal is measured as a function of the wave number ( k ). By virtue of the definition of OTDR and OFTR, the scheme of distributed interference used in the instant invention can be categorized as a method of optical wavenumber domain reflection measurement (OWDR).

The sensitivity of this embodiment and the changes of the embodiments of the first and third groups to the amplitude of the in-focus image is substantially simultaneous with respect to all axis positions accessible to the given exposure as a result of the combination of OWDR. For this embodiment and modifications of the second and fourth group of embodiments, the sensitivity to the amplitude of the in-focus image is essentially the same as the optical axis of the subject material imaging subsystem accessible to the given exposure as a result of the combination of OWDR But also for all lateral positions in the vertical line section. The standard confocal interference microscopy system must perform a scan on the dimensions of the individual axes or the rearward dimension of the object of interest to obtain an equivalent sensitivity to the amplitude of the in-focus image.

An unusual characteristic of the confocal interference microscope in this embodiment and variations of the first and second group of embodiments is that it obtains information about the points of the array in the image substantially simultaneously. The confocal interference microscopy system has sensitivity to a reduced out-of-focus image, as compared to that obtained with prior art confocal interference microscopes, and reduces the effect of the out-of-focus image, Is known as a means for improving light sectioning for the purpose of obtaining two-dimensional, two-dimensional, three-dimensional images. (See M. Born and E. Wolf's Optics Principle 8.6.3., Pp. 423-427 (Pergamon Press, New York) 1959) have been used to improve the contrast for a particular application And the manner of OWDR used in DIP is known as a means to reduce phase ambiguity. However, it is believed that the combination of confocal interference microscopy, change in pupil function, and OWDR in the same system for the reduction of statistical and systematic errors resulting from the background light is taught herein by the present inventors for the first time.

The unusual characteristics of the confocal interference microscope of the variants of this and third and fourth group of embodiments are that they each have substantially reduced sensitivity to the out-of-focus image of the prior art confocal interference microscope And obtain information about the array of points in the image substantially simultaneously. Confocal interference microscopy is known as a means for reducing the effects of out-of-focus images, and the scheme of OWDR as used in DIP is known as a means of reducing ambiguity in phase. However, it is believed that the combination of the confocal interferometer microscope and OWDR in the same system for the purpose of reducing statistical and systematic errors arising from background light is taught for the first time in the art.

The unusual characteristics of the confocal interference microscopes of the variants of this and fifth group of embodiments are that they each have sensitivity to a reduced out-of-focus image compared to that obtained with prior art confocal interference microscopes, Which is related to the ability to obtain information about the array of points in the first and second groups of embodiments.

Thus, it is believed that the combination of confocal interference microscopy and pupil function deformation in the system for the purpose of reducing both systematic errors and statistical errors arising from background light is first disclosed by the inventors herein.

Impulse response function for infocus image: OWDR of axis

The first embodiment depicted in Figures 1a-1n has been adopted in the system to demonstrate the principles of specific features authenticated in the previous section, and the principles of which are described in the four embodiments and variations . While each pixel of detector 114 in Figures IJ, IK and 1N senses the optical frequency component of the light beam as a result of the dispersion detector components 130a and 130b shown in Figure Ia, The spatial filter pinhole 18a in Figs. 8 (h) and 1 (h) and 1 (i) and 1 (m) represents the conjugate pinhole of the confocal interference system for all optical frequency components of the light beam. It is possible to reconstruct a substantial equivalent to a prior art confocal signal suitable for each accessible axial position from the intensity recorded by the detector 114 as a function of the optical frequency in the four exposures of a set, appear. This is because the physical scan in the axial direction of the subject material shown in Figs. 1C and 1E, as a function of the axial position, as compared to the standard confocal microscopy system required to obtain the confocal signal of the prior art, Focus confocal signal as an equivalent prior art function as a function of the condensing position with which it is located.

Two useful non-holographic confocal scanning microscopic modes [Progress in Optical and Electron Microscopy: C.J.R. Sheppard, "Scanning Optical Microscopy", 10, (Academic, London, 1987); C.J.R. Sheppard and A. Choudhury, Optica Acta, 24 (10), 1051-1073 (1977)): There are a reflective mode and a transmissive mode. Indeed, it is easy to make a reflective mode microscope that makes an optical separation by scanning an object along the direction of the axial direction (CJ R. Sheppard and C. J. Cogswell, J. Microscopy, 159 (Pt 2), 179-194 (1990); C. J. R. Scheppard and T. Wilson, Optics Lett., 3. 115-117 (1978); C.J.R. Sheppard, D.K. Hamilton, and I. J. Cox, Proc. R. Soc. Lond., A 387, 171-186 (1983)].

Consider the confocal microscope shown in FIG. 5 with three imaging portions. The lens 1 of FIG. 5 for the combination of the source 10, the object 112 and the subsystem referenced in FIGS. 1A-1N including the probe beam and the detector 114 for the scattered probe beam is shown in FIG. The combination of the lens 16 of the illustrated subsystem 81, the lenses 26 and 36 of the subsystem 81 shown in FIG. 1C, and the lens 46 of the subsystem 82 shown in FIG. Equal; The lens 2 of Figure 5 is equivalent to the combination of the lens 46 of the subsystem 82 shown in Figure 1f and the lens 26a of the subsystem 81a shown in Figure 1h; The lens 3 of Figure 5 is equivalent to the combination of the lens 36a of the subsystem 81a shown in Figure 1h and the lens 66 of the subsystem 84 shown in Figure 1j. The lens 1 of FIG. 5 for the combination of the subsystem referenced in FIGS. 1A-1N, including the source 10, the object 112, and the detector 114 for the reference beam and the reflected reference beam, the lens 16 of the subsystem 80 shown in Fig. 1B, the lenses 26 and 36 of the subsystem 81 shown in Fig. 1C, and the lens 56 of the subsystem 83 shown in Fig. ); ≪ / RTI > The lens 2 of Figure 5 is equivalent to the combination of the lens 56 of the subsystem 83 shown in Figure Ig and the lens 26a of the subsystem 81a shown in Figure 1i; The lens 3 of Figure 5 is equivalent to the combination of the lens 36a of the subsystem 81a shown in Figure 1i and the lens 66 of the subsystem 84 shown in Figure 1k.

We have four spaces each with i = 1 0, 2 and 3; The imaging plane space 7A, the space of the target material 112, the space of the reference mirror 120, the space of the imaging plan 17aA, and the imaging plane space 47A, Defined as:

Where sin? _I is the aperture ratio of the region i, frequency Is the radian wavelength in vacuum, and and Is the optical path distance in the region i. The optical path distance

, Where the integral follows each ray path Location .

Imaging in a confocal scanning microscope moves to a coherent microscope (Sheppard and Choudhury, ibid.), Which can be described by a coherent transfer function, and the coherent transfer function is a pre-conversion of the impulse response function . Thus, an efficient three-dimensional impulse response function for the system in FIG. 5 The

, Where < RTI ID = 0.0 >

h _i , P _i , and W _i are the impulse response function, the papil function, and the wave aberration function [cf.Ref. 1, 2, 3, and 4 respectively for the i th equivalent lens in FIG. 10-12 in M. Gu and CJR Sheppard, Appl. Opt., 31 (14), 2541-2549, (1992); j is (-1) ^1/2 . The impulse response function is the amplitude in the imaging plan that corresponds to the source of a point. The function of the phase converter 44 is integrated into an appropriate puff function P _i .

The scattering distribution t (v ₀ ) [cf. CJR Sheppard and XQ Mao, J. Opt. Soc. Am. A, 6 (9), 1260-1269 (1989)], and the scattering distribution t (v ₀ )

To the refractive index n [E. Wolf, Opt. Commun., 1, 153-156 (1969). Both n and t are generally complex, and j in Eq. 5 is a wave that is scattered in a lossless medium and is quadrature to the direct wave. I think the influence of multiple scattering is negligible. Also non-scattered radiation is neglected, which is a reasonable assumption for radiation mode microscopy because direct (non-scattered) radiation does not contribute to imaging. The imaging size can be summed over the basic slices that make up the object because the principle of superposition is reasonable. Moreover, the imaging magnitude should be integrated for an incoherent source of size distribution A (v ₁ ). The attenuation function a (v ₀ ), which represents the attenuation of the radiation at the object, should also be included in both incident and scattered radiation.

The impulse response function of the lens including the dispersion detector elements 130a and 130b is

, Where < RTI ID = 0.0 >

And G ₃ (k, v ₃ ) is a distributed fuzzy function for the dispersion detector elements 130a and 130b in FIG. 1A. Expression u sign change of in the formula (7a) and (7c) with respect to u represent conforming to (7a) is due to reflection occurring at v ₀ space.

The size of the scattered probe beam U _s in the imaging plane 17a of the spatial filter pinhole 18a is given by:

Where R ₁ and T ₁ are the reflection and transmission coefficients for the beam splitter 100, respectively.

Substituting equation (6a) and (6b) in the expression (8) is obtained in the following expression for U _s (v _2).

The size U _s (v ₂ ) represents the complex scattering amplification for the inventive device in the spatial filter pinhole 18a in FIG. It follows from the characteristics of the impulse response function h _e (v ₃ , v ₂ , v ₀ , v ₁ ) given by equation (3) and the complex scattering in the imaging plan 47 of the detector 114 shown in FIG. The amplification U _s (v ₃ ) is obtained by multiplying the impulse response function h ₃ (v ₃ -v ₂ ) for each combination of the lenses 36a, 66 of Figs. 1h and 1j with the dispersion detector elements 130a, ) ≪ / RTI > of U _s (v ₂ ). The optical coordinates of the imaging plan 47 are given by v ₃ . Expressed in terms of equations,

Here, t ₂ (v ₂ ) is a transfer function for the spatial filter pinhole 18a. The appropriate equation of U _s (v ₃ ) for the transmission mode confocal microscope configuration is set (10). ≪ / RTI >

When used in the apparatus of the present invention, it readily identifies the important characteristics of OWDR without causing undue complexity by examining the observed magnitude characteristics of the interference signal resulting from scattering by the planar cross-section of the object. With this in mind, we first introduce an arbitrary three-dimensional (1, 2, 3, 4, 5) The response of the confocal interference microscope to the plane cross-section of the scattering object was considered.

Let the size of the reflected reference beam in the imaging plane 47 of the detector 114 be U _R in Figure 1K, with the axial position of the reference mirror and the transverse portion of the scattering object at z _{0, R} and z _0, Let U _R have the appropriate change in the variable and can be obtained from Eq. (10). The output current I from the detector 114 for a given cross-sectional plane portion of the scattering material is such that f ₃ is the focal length of the detector region 3, Is the v ₃ component of the spatial frequency characteristic for the used diffraction orders of the dispersion detector elements 130a, 130b, Is the phase difference between U _S and U _R at z _{0, S} = z _{0, R} , and χ is the phase difference between U _S and U _{R at R} in phase detector 44 of the interferometer in subsystem 83 shown in FIGS. Which is the phase shift generated by the phase shifter.

The constant magnitude in Eq. (11b) and the term in the topological element proportional to the scattering magnitude of χ are found at four different values of χ Can be obtained by the measurement of < RTI ID = 0.0 > A set of four preferred values of χ are χ = χ _0, χ ₀ + π, χ ₀ + (π / 2), and χ ₀ + (3π / 2). The corresponding four values of the output current I _i for each of i = 1, 2, 3, and 4 are combined to follow the next schedule.

The complex representation for [Delta] I is defined as

Or by substitution of equations (13a) and (13b).

With respect to the material to be scattered with a limited axial thickness, For z _{0, S} ≪ / RTI > Using equation (15) Can be expressed for a scattering target material having a limited axial thickness as follows.

Termination signal As a function of v ₃ As a function of frequency k.

The observed amount [Delta] I in a constant size element is indicated by an examination of equation (16), which is the Frie transform for the product of the scattered size U _S and the reference size U _R. Prior art confocal interference microscopes obtain the same information about the material of interest. z For an array of axis points in the ₀ direction, Is obtained as an apparatus of the present invention from four independent measurements obtained continuously in time without scanning of the required material of interest. For prior art confocal interference microscopes, equivalent four independent measurements must be made for each axis point in the array of axis points in the z ₀ direction by scanning the material of interest. like this, The information presented is obtained for the material of interest with the device of the present invention in less time than the prior art interference confocal microscopes. This feature of the instant invention leads to a partial improvement in statistical precision and reduced sensitivity to the movement of the material of interest during acquisition of the measured current.

Characteristics of amplified scattering amplification

The measured intensity I _i can be combined to give ΔI when expressed by the formula (16), which is the pre-conversion of the product of the scattered amplification U _S and the reflected reference amplification U _R. "The impulse response function "Appears in the section titled. Thus, the information about the scattering object itself can be obtained with respect to the frequency k Can be obtained by calculating the inverse free transform F ^-1 ([Delta] I). In other words,

Substitution of the expression for ΔI given by equation (17) into equation (17) yields the following equation for the products of scattered amplification U _S and reflected reference amplification U _R :

Based on equation (18) From The procedure for calculating on And the reflected amplification Is determined by independent measurement. In the calculations referred to, all of the non-subject materials related to ψ _R It is important to know your contribution to. The method of determination consists of three different types of measurements. The first type of measurement is made with the target material 112 replaced by a planar reflective surface known as a reflection characteristic for making a measurement corresponding to the complex amount < RTI ID = 0.0 > From the corresponding complex amount < RTI ID = 0.0 > I < / RTI & ≪ / RTI > is obtained, silver All non-target materials that contribute to The second type of measurement is to measure one of I _i without the target material. From I _i obtained without the target material Is obtained. The third type of measurement is to measure one of I _i with a reference material 112 replaced by a planar reflecting surface known as a reflection feature and without a reference mirror. A measurement of | U _{S, 0} | is obtained from I _i obtained with the target material 112 replaced by the reference mirror and by the planar reflecting surface. Three sheep , | U _R | ² , and | U _{S, 0} | The measurement of ² From For use in the calculation of And the like.

The accuracy with which this procedure can be determined will depend in part on the background of the device of the present invention, the level of background created by the device itself, not by the material of interest. The method described also includes: | U _{S, 0} | ² and the material of the object of the interferometer of the apparatus of the present invention can be used to characterize the impulse response function.

The axial resolution of the device of the present invention is easily estimated for cases where the axial resolution determined by the numerical aperture of the device of the present invention for a given wavelength is exceeded. The following simplifying assumption is made to estimate the axial resolution for such a state without confusing or distributing pictures with non-intrinsic items. | U _R || U _R | And (? _{S -} ? _R ) vary by a negligible amount with respect to the interval of k_to k ₊ , and the spectrum of the source also has a trigonometric function , The integral for k 'in Eq. (17) can be approximated to the following form of the result.

here,

From the equation (19), | U _S | can be obtained with the following axial spatial resolution

It is expressed by an item of the following wavelength.

here,

White light fringe pattern

For an example of a scattering object that is a single reflecting surface, ΔI is a typical white light fringe pattern determined by the numerical aperture of the device of the present invention for a given wavelength when the axial resolution is exceeded. Consequently, for such a situation, the relative position of the reference and the reflective surface of the object can easily be identified with an axial resolution similar to that given by Eq. (22a) or Eq. (22b). This is obtained directly from the white light fringe pattern by either the peak position in the fringe pattern with the largest amplification, the peak position in the envelope of the white light fringe pattern, or some other contrasting reference feature. (cf. Refs. 2-7 in L. Deck and P. de Groot, ibid.).

Impulse response for in-focus imaging: transverse OWDR

The fifth embodiment of the second embodiment group illustrates the principle of the distinguishing feature cited in the section entitled " background correction " although the basic principle applies well to all embodiments of the second embodiment group and its variants The system was adopted. As to the fifth embodiment, the impulse response function for in-focus imaging for a confocal interference microscopy system using OWDR is readily obtained from the impulse response function deduced in the preceding section for the first embodiment; The function P _{i of} the first embodiment is replaced by the corresponding function of the fifth embodiment and the function P _{i of} the fifth embodiment is the same as that of the dispersive components 130a, 130b, 130c, and 130d , 2aa, 3aa, and 4aa).

The observed amount, ΔI, in the constant-magnitude component is indicated by the investigation of the pre-conversion probability (16) of the product of the scattered amplification U _S and the reflected reference amplification U _R.

Prior art confocal interference microscopy obtains equivalent information for the material of interest. For the target material in the array of side points in the portion of the transverse plane Is obtained by the apparatus of the present invention from four independent measurements that are obtained continuously in time without scanning of the required material of interest. For prior art confocal interference microscopes, equivalent four independent measurements must be made for each side point in the array of side points in the transverse plane portion by scanning the material of interest. like this, Can be obtained for the target material with the apparatus of the present invention in less time than in prior art interference confocal microscopes. This characteristic of the instant invention leads to a partial improvement in the accuracy of the target material and the reduced precision in the movement of the material during the acquisition of the measured current.

Amplification of out-of-focus imaging

The amplification of the out-of-focus beam U _B at the spatial filter pinhole in the imaging plane 17a can be expressed in terms of Fresnel integrals C (z) and S (z), which are defined as follows.

[cf. Abramowitz and Stegun, Handbook of Mathematical Functions, (Nat.Bur.of Standards, Appl. 7.3, 300-302, 1964]. The expression for U _B can be expressed for a point source 8 located at v ₁ = (0, 0, 0)

Here, f ₂ is the focal distance of the zone (2) in Fig. _{5, (x 2, y 2} , z B) is out of the imaging plan 57-of-a focus coordinates, (A _B / f ₂ Is the out-of-focus amplification in the exit pupil of the lens 2,

Wow (Derived from the diffraction theory introduced in section 8.8.1 of Born and Wolf) of lens 2. (2) without apodization of the phase shifter component of the phase shifters 14, 24, and 34, and The integration results for

here,

, A is ζ ₂ and Lt; / RTI > is the width of the stator component in the direction. m = 2 and without the apodization of the phase shifter components of phase shifters 14, 24, and 34, The results for the level (1) discriminating action for the example in the direction are as follows.

For each beam B52D-1, -2, -3, -4 for level (1) discrimination, An example of y = 0 For Lt; / RTI >

It is evident by the investigation of FIG. 6 that the device of the present invention exhibits reduced sensitivity to background from out-of-focus imaging, compared to prior art interference confocal microscopes, 17a), the prior art interference confocal microscope responds to U _B , while the prior art interference confocal microscope responds to U _B for the x ₂ and y ₂ as a result of the antisymmetric spatial property of U _R. In the spatial filter pinhole 18a, The integration of the optical frequency components of the corresponding detector pinhole The approximation equivalent to the integral of the Fresnel interval [cf. Abramowitz and Stegun, ibid.] And operate in the manner listed in Table 1 for both the case of prior art confocal interference microscopes and the invention disclosed herein. In Table 1,

U ^* represents the complex conjugate of U, the integral U _R is the level (1) a central position with respect to the in x ₂ for discrimination, and the level (2) inverse symmetrical position in both x ₂ and y ₂ of the discriminant Spacing.

In contrast to the background from the out-of-focus imaging out of the range of Table 1 given, the improved discrimination results in the phase shifter configuration of the phase shifters 14, 24, and 34 to reduce the magnitude of the derivative of U _B for x ₂ and y ₂ Lt; / RTI > is obtained in the apparatus of the present invention by apodization of the element. Apodization function Watch.

Level (2) discrimination and at m = 2 and The result after integration is as follows,

here,

In the spatial filter pinhole 58, The integration of the optical frequency components of the corresponding detector pinhole Is very close to the characteristic of the Fresnel interval [cf. Abramowitz and Stegun, op. (2) discrimination with apodization given by equation (31) and In a direction Dependent Lt; RTI ID = 0.0 > (1) with no apodization in the direction of the direction shown in Table 1 for the invention disclosed herein.

A very simple feature of the apparatus embodying the present invention is the enhanced attenuation of the filtered interference spectra, the spatially filtered reflected reference beam, and the filtered wave number, and the spatially filtered background beam Is efficient for each independent volume component of the out-of-focus imaging source. Therefore, the reduction leads both to enhanced reductions in systematic errors made by the background from out-of-focus imaging as well as reductions in statistical reductions.

The potential value of the de-piping capability for the reduced sensitivity of the apparatus of the present invention to the background from the out-of-focus image is also effectively reduced compared to the axial securing power of the prior art confocal microscopes Lt; RTI ID = 0.0 > of the axial confinement < / RTI > The detected interference between the reflected reference amplification and the background amplification from the out-of-focus image. The error signal in the prior art interference confocal microscope due to the cross term is detected from the out-of-focus image intensity and less dependent on the z _B z _B by the primary in comparison with the error signal in the prior art caused by confocal microscopy.

Statistical error

Let's look at the response of the device of the present invention to the planar cross-section of any third-order scattering object 112. The output current I from the detector's pixel for a planar portion of a given cross-section of the scattering object 112 is of the form

Integral Is the integral over the area of the detector pinhole, and [ chi] is the phase shift resulting from the phase shifter 44. [ Equation (12a) and the corresponding equations for the intensity difference defined by the _{(12b) Δ I 1 = I} 1 - I 2 and _{Δ I 2 = I 3 - I} 4 are each

And I _i is defined by the following equation.

And Can be expressed as follows.

In the derivation of equations (37a) and (37b) And , I.e. the statistical noise in the system is determined by the Poisson statistic of the number of detected light emitting electrons And Both are assumed to correspond to many light emitting electrons. And , The term depending on U _S in the right side of the equations (37a) and (37b) can be ignored and is derived as a simple equation as follows.

from Obtained when going to And The additive gain in the signal-to-noise ratio for the signal-to-noise ratio is almost (3/2). However, this latter gain is obtained at the expense of a significant increase in the required dynamic range and source power of the signal processing electronics. therefore, Lt; / RTI > is typically < RTI ID = 0.0 >

When the condition expressed in equation (39) is satisfied, the statistical error given by equation (38a) and (38b) is limited as expressed in the following inequality.

In the discussion of equations (37a) and (37b) or (38a) and (38b), an apparatus embodying the invention with a reduced background of the device from an out-of-focus image is essentially a prior art confocal interference micro- Lt; _{RTI ID = 0.0 >} U _S &_lt; / _{RTI >} and U _R as compared to the scoping system. Typically, the signal-to-noise ratio obtained when using the apparatus embodying the present invention will be larger by (3/2) ^1/2 than that obtained by the confocal interference microscope that does not use the invention disclosed herein.

The interpretation of equations (37a) and (37b), equations (38a) and (38b), and equations (40a) and (40b) is as follows: By the invention published here, complex scattering amplitudes And thereby the statistical error for each of the components of the complex scattering amplitude inferred for each independent position of the object is typically determined by the statistics of the complex scattering amplitude itself, ) ^1/2 and the mentioned statistical errors can be obtained with a lower required dynamic range capacity in the signal processing electronics and a lower operating power level of the source compared to prior art confocal interference microscopes. The term independent position is used to mean that the association set of four measurement intensities is a statistically independent set.

The first and second embodiments illustrated in Figs. 1A-1N and Figs. 2A-2F and the transmission of the scattered probe beam and the phase shifter 24 for simultaneously attenuating the out-of-focus image beam at the image plane 47 (39) for the first and second modified embodiments, which are implemented by shrinking the first and second modified embodiments. In order to obtain a given signal-to-noise ratio, this attenuation procedure may require an increase in the intensity of the light source 10 as the attenuation in the phase shifter 24 increases. Alternative third and fourth embodiments and third and fourth modified embodiments of the invention illustrated in Figs. 3a-3l and 4a-4f are similar to the transmission / reflection of beam splitter 100 , 100a , and 100b By adjusting the properties proportional to each other, the conditions given by Eq. (39) are met. When any one of the third or fourth embodiment is used to satisfy the condition expressed by the equation (39), the light source 10 or 10a is generally controlled by the attenuation procedure based on the reduction of the transmission of the phase shifter 24 It can be operated at a lower power level than required.

The signal-to-noise ratio can be adjusted, for example, as a function of wavelength of the source optical frequency component to generate a signal-to-noise ratio for the primary independence of the wavelength. This characteristic has been described in the section introducing the detailed description of the first embodiment. As indicated in the cited description, the scattered probe beam P42D , which has been filtered and spatially filtered with a wavelength perpendicular to the corresponding optical frequency component of the amplitude of the probe beam P22D prior to penetration into the target material 112 The amplitude will vary with the wavelength due to the stated factor. The amplitude ratio of the scattered probe beam P42D filtered and spatially filtered to the wavelength for the amplitude of the background filtered beam spatially filtered background beam B62D is also generally proportional to the image point 28 into the object material 112. [ Will decrease with increasing depth. The effect of such a factor in the signal-to-noise ratio can be partially compensated by placing the wavelength filter in the reference mirror subsystem 83 and / or the effect of such a factor in the noise ratio can be achieved by placing the wavelength filter in the reference mirror subsystem 83 and / / RTI > and / or the conditions represented by the scattered probe beam P42D filtered by spatially filtered and scattered probe beam P42D and by equation (39), by positioning in the probe beam subsystem 82 , preferably the reference mirror subsystem 83 , In order to adjust and / or optimize the ratio of the filtered and spatially filtered reflected reference beam R42D to the wavelength transmitted through each detector pinhole to ensure that other wavelengths are satisfied, So that it can be partially compensated.

System error due to out-of-focus image

Equation (35a) and (35b) is ΔI _1, ΔI _2, and to measure real and imaginary parts of the U _S ≪ / RTI > Can be determined, for example, by the method described in the section entitled " Characteristics of Fourier Transformed Scattering Amplitude ". Potential grid error term remains.

This grid error term It can be important. As a result, it is preferable that the interference terms expressed by the equations (41a) and (41b) are compensated with an allowable level.

In the invention published here And Compensation for the term generally requires fewer than is required in the prior art confocal interference microscope for computer processing. This is because the spatial properties of U _B depend on the scattering characteristics of the three-dimensional target material 112 under consideration and therefore depend on U _S through the integral equation. These integral equations (35a) and (35b) are integral equations of the Fredholm class II. The computer processing required to perform the inverse of each integral equation for obtaining U _S is the same as in the apparatus implementing the present invention And Decrease as the term shrinks. In general, the reduction ratio in the required computer processing is And It is faster than the reduction ratio of the protest.

Mutual interference term For the contrast to that does not compensate them interferometric measurement according to the apparatus for implementing the present invention, the integral equations corresponding to the equation (35a) and (35b) are nonlinear integral equations: the equations in the U _S This is the second integral equation. Nonlinear integral equations generally require considerably more sophistication than required by linear integration equations for computer hardware and software for that solution. From working in terms of And The conversion by an apparatus embodying the present invention in accordance with the present invention represents an important feature of the present invention over the prior art pinhole confocal microscopy.

In an apparatus embodying the present invention, It is also noted that the reduction of systematic errors due to the pinhole confocal microscope, which is the prior art, is perfect in comparison to that obtained.

Wide-area operation

It is noted that the enhanced reduction of the background effect from the out-of-focus image is effective when the source 10 is a wide-area source, as is required for simultaneous imaging of multiple image points in the axial direction of the probe lens 46 It is one of the important characteristics. To discuss this property, and herein above functions W _i = 1 for the sake of simplicity in peopil function P _i does not have Affordable die Localization (apodization), i.e. Affordable die of the phase shifter (14, 24, 34, 34a , and 44) It is assumed that there is no. When the apodization is used to correct the result, for example, the resulting mathematical expression for U _S ( v ₃ ) will be more complex, but nevertheless generally has important properties, for example symmetry or anti- A person skilled in the art will recognize.

For the case of level 1 discrimination under the assumption for the simplification cited in the previous section, the integral of Eq. (9) is

The A 'and d ₀ are replaced by phase shifters 14 , 24 , 34 , and 34a , respectively, Lt; RTI ID = 0.0 > distance < / RTI > w _i dependency is suppressed because it is not related to level 1 discrimination for reduction of the background from the out-of-focus image, and the spatial property of U _S ( v ₂ ) in the υ ₂ direction is filtered by the wave number and spatially filtered ≪ / RTI > is then arranged to obtain an enhanced reduction of the backgrounded beam and consequently a limit potential source in the wide-angle operation.

The corresponding expression for the amplitude of the reflected reference beam U _R ( v ₂ )

ego, The .

Consider a special case where a '= d ₀ . In that case, Eqs. (42) and (43) are reduced as follows.

The integration for υ ₀ in Eq. (45) can be performed as follows.

U _R (v ₂₎ For two element phase shifting system (m = 1) y ₂ = 7 to 0, z ₂ = 0, and υ ₁ = about _{0 (x 2 kd 0 / f} ) of the Function.

The antisymmetric spatial distribution of U _R ( v ₂ ) for υ ₁ is It is apparent from equation (46) through the factor. The spatial distribution of U _S ( v ₂ ) generally shows a similar tendency because Eq. (44) is a mathematical structure like Eq. (45). It is an antisymmetric spatial distribution developed in the first reduction of the background amplitude from the out-of-focus image.

Expression from the system characteristics as shown in (46), U _S given by equation (44) (v ₂₎ to phase (υ ₂ -υ ₁₎ is one which satisfies the following conditions: for-high with respect to the focus image It is clear that the sensitivity is maintained.

[σ ( q )] ² is the variance of the variable q.

contribution to the signal for a given value of (υ ₂ -υ ₁₎ is _{(x 2 - x 1) /} f and has a hyperbolic relationship between k, (υ ₂ -υ ₁₎ is k (x ₂ - x ₁ ) / f . Thus, the corresponding permissible values of k and ( x ₂ - x ₁ ) / f satisfy the equation (47), and a detector that will yield an improved signal-to-noise ratio (with respect to the in-focus signal strength for out- There may be a limit on k to allow the image to be obtained. The following relationship is obtained from equation (47).

For the discussion presented here, if we choose to operate in a mode where each of the two terms on the left-hand side of Eq. (48) contribute equally to the left-hand side, we get

And

The equation for ( _k / k ) is obtained by combining the following equation with equation (50).

r π denote a subset of the (ν _{2 -} ν ₁ ) values that cause a peak at the next factor.

The results are as follows.

It is evident from equation (53) that an apparatus embodying the invention for a relatively wide operation in lambda is valid. For example, for m = 1 and r = 1 And for m = 2 and r = 1 to be.

There is a limit to the range of r values that can be used effectively. This limit is due to the consideration of the signal-to-noise ratio. For each peak in the factor given by equation (52) contributing to the observed signal, the signal strength is improved. However, as the increase in the number of included peak, and therefore the maximum value of r, r _max is increased, the bandwidth on k must be reduced according to the expression (53).

There is also a limit to the spacing between the source pinholes when using level 2 discrimination in each modified form of either the second or fourth embodiment of the present invention and the detailed description of the second and fourth embodiments . This restriction can be obtained using an analysis similar to the analysis type of the section on wide-area operation. From the system characteristics as shown in equation (46), it is clear that a high sensitivity to U _S ( v ₂ ) is maintained for an in-focus image as long as the following condition is satisfied.

δ v ₁ is the interval between the adjacent pin holes of the pinhole respective linear array source.

Note that the right side of the equation expressed by equations (49) and (50) does not explicitly depend on x ₁ or y ₁ . Thus, the apparatus embodying the invention acts on points such as the source without inherent limitations on the range of values for x ₁ and y ₁ .

Observation through turbid medium

Another important feature of the invention disclosed herein is that enhanced reduction of the out-of-focus image background effect can be effective when viewed through a coarse medium. For observations through a coarse medium, the impulse response function h _{A, M} is

h _A is the impulse response function for the device when viewed through the non-tangible medium, h _M is the impulse response function for the coarse medium, and * indicates the convolution of h _A and h _M. h * h _A Fourier transform F (h _A h * _M) of _M is as follows.

The impulse response function h _M is well represented by the Gaussian distribution.

σ ₂ is the variance of h _M.

Fourier transform F (h _M) of _M h is given by:

q is a space angular frequency vector in conjugation with v . The lowest frequency peak in h _A is located at the next frequency.

_A relatively large value for h _{A, M} is maintained at q = ( d ₀ / λ) in the following cases: This is apparent from equations (56) and (58).

or

When using equations (59) and (61), the value of d _{0 that} can be used is limited by the following conditions.

It is therefore possible to configure the tomographic imaging system embodying the present invention to maintain a relatively high sensitivity to spatial frequencies below the cutoff frequency imposed by h _M.

According to the present invention, the interference term between the amplitude of the background light (i.e., the out-of-focus return probe beam) and the reference beam for the reference beam amplitude of any spatial characteristic can suppress the occurrence of unwanted systematic errors, It will be appreciated that this will be important in the occurrence of non-statistical errors. The interference terms between the amplitudes of the background light and the reference beam will be reduced in the above embodiment of the present invention due to the antisymmetric spatial property calculated for the reference beam for phase shift. Since this interference term will be reduced, it does not cause the generation of unacceptably large grid errors and statistical errors on the data produced by each pixel of the multi-pixel detector.

The interference between the spatially filtered reflected spatially filtered and spatially filtered reflected reference beam and the spatially filtered scattered probe beam (i. E., The " desired signal "), filtered with the amplitude and wave number of the spatially filtered and spatially filtered reflected reference beam, It is recognized that the term is related. The reference beam is detected as a square of the reflected reference beam amplitude filtered by the wave number and spatially filtered. The wavenumber filtered and spatially filtered scattered probe beam is filtered by a wavenumber and filtered spatially filtered reflected reference beam and a spatially filtered spatially filtered scattered probe beam, i.e., a wave-filtered and spatially filtered, Is detected as an interference term between the amplitudes of the spatially filtered probe beams filtered with the wave number multiplied by the amplitude of the reference beam. Thus, the filtered and spatially filtered reflected reference beam and the detected wavenumber filtered and spatially filtered scattered probe beams filtered with the detected wave number are filtered out and the amplitude of the spatially filtered reflected reference beam is present in each This is relevant. This relationship makes the determination of the material properties of the object from such an interference term statistically more accurate. As a result, the exact nature of the material of interest can be determined from the data produced by the multi-pixel detector in response to the interference terms between the spatially filtered reflected spatially filtered reflected reference beam and the spatially filtered scattered probe beam Can be obtained. This is because the statistical accuracy obtained for a given pixel of the multi-pixel detector is not wastewater filtered and spatially filtered to a square or wavenumber of the reflected reference beam amplitude and a square of spatially filtered background beam amplitude Is limited by the number of photoelectrons calculated in the pixels that are filtered out of the wave and spatially filtered to respond to squares of the scattered probe beam amplitudes.

It will be further appreciated by those skilled in the art that alternative and / or additional optical elements and detectors may be integrated into one of the published embodiments of the present invention. For example, a polarized beam splitter may alternatively be used or may be used with additional phase shifting elements to change the radiation characteristics used to probe the material of interest. A further example would be the addition of a detector to monitor the intensity of the light source. These and other obvious variations will be introduced without departing from the spirit and scope of the present invention.

Phase shifter 34 is For example, you could be omitted in FIG. 1a-1n, the image of the point light source (8) determined in the image point 38 in the image plane 37 in which case the image of the image plane (47) It will also be appreciated that although the image of the point light source 8 produced by the reflected reference beam at point 48 will not change from this to the large volume. Nevertheless, the erasure of the out-of-focus image will be accomplished. Similarly, phase shifter 34 may be omitted in Figures 2a-2f and phase shifters 34 and 34a may be omitted in Figures 3a-3l and 4a-4f .

The spatial configuration of the phase shifter elements of the phase shifters 14 , 24 , 34 , and 34a may also be such that the spatial distribution of the reflected reference beam amplitudes in a single pixel detector yields a spatial counter- It will be appreciated that this may be different from what has occurred. However, the image data produced by the multi-pixel detector may need to be processed slightly differently for this embodiment of the present invention to produce the desired tomographic image of the material of interest 112 .

It will be appreciated by those skilled in the art that the interferometer of the embodiments and modified embodiments of the invention described herein can be configured as a confocal interferometer microscopy mechanism that functions in a transmission mode without departing from the spirit and scope of the present invention. The transmission mode may be a preferred mode of operation in any of the read and write modes of the present invention, such as when the detection is changed in the polarization state of the probe beam.

It will further be appreciated that the interferometer of this embodiment may be in a polarized form, for example, to probe the object material 112 with polarized light or to increase the throughput of light through an interferometer to a single or multi-pixel detector. However, additional optical elements, such as a polarization beam splitter, will need to be added to the apparatus for the purpose of mixing the reflected reference beam and the scattered probe beam in a single or multi-pixel detector.

Claims (44)

A method of identifying an in-focus image of an area on and / or within an object from an out-of-focus image to reduce errors in image information of the object, (a) generating a probe beam and a reference beam from a monochromatic point source; (b) generating a contrary spatial spatial property to the reference beam; (c) generating an in-focus return probe beam by directing the probe beam to an in-focus on or within the region; (d) generating an opposing spatial characteristic to the in-focus return probe beam; (e) interfering the beam from the reference beam and the out-of-focus image point of step (b); (f) interfering the reference beam of step (b) and the in-focus return beam of step (d); And (g) an interference term between the reference beam of step (b) and the in-focus return beam of step (d) by the detector system to reduce errors in the data produced by the detector system to represent the image information, Detecting the amplitude of the interference term between the amplitude of the reference beam and the out-of-focus image beam of step (b) to be substantially reduced, as the amplitude of the in-focus returning probe beam . The method according to claim 1, Wherein the point source is a point on a monochromatic line source. The method according to claim 1, Wherein the object is a semiconductor wafer. The method according to claim 1, Characterized in that the object is a biological entity. The method according to claim 1, Characterized in that the object is an optical disc and the region is a region containing information on the optical disc and / or in the optical disc. A method of identifying an in-focus image of an area on and / or within an object from an out-of-focus image to reduce errors in image information of the object, (a) generating a probe beam and a reference beam from a broadband point source; (b) generating a contrary spatial spatial property to the reference beam; (c) passing the probe beam through a first diaphragm element to convert the probe beam into a focused beam on an object and / or a line therein; (d) generating an in-focus return probe beam; (e) generating a contrary spatial spatial property to the in-focus return probe beam; (f) spatially filtering the in-focus returning probe beam of step (e); (g) passing a spatially filtered beam through a second diaphragm element to convert the spatially filtered in-focus return probe beam into a focused beam in a line of the detector plane of the detector system; (h) spatially filtering the reference beam of step (b); (i) passing a spatially filtered reference beam through a second disparity element to convert the spatially filtered reference beam into a focused beam in a line of the detector plane of the detector system; (j) spatially filtering the beam from the out-of-focus image point; (k) passing a beam spatially filtered from an out-of-focus image point to a focused beam at a line of the detector plane to a beam spatially filtered from the out-of-focus image point, ; (l) interfering the focused spatially filtered beam of step (k) and the focused spatially filtered reference beam of step (i) from an out-of-focus image point; (m) interfering with the focused spatially filtered reference beam of step (i) and the focused spatially filtered in-focus return beam of step (g); And (f) of said step (i) by means of a detector system to reduce errors in data produced by said detector system to present image information of said object (n) (Ii) the interference terms between the focused spatially filtered in-focus return beams and the spatially filtered reference beam amplitudes of said step (i) being substantially reduced and the spatially filtered out- And detecting the amplitude of the interference term between the amplitudes of the focus image beam. The method according to claim 6, Wherein the point source is a point on a broadband line source. The method according to claim 6, Wherein said step (c) comprises passing a probe beam through at least one grating, said line being substantially parallel to a surface of an object. The method according to claim 6, Characterized in that the line is substantially perpendicular to the surface of the object. The method according to claim 6, Further comprising performing a Fourier transform on the data produced by the detector system. The method according to claim 6, Wherein the object is a semiconductor wafer. The method according to claim 6, Characterized in that the object is a biological entity. The method according to claim 6, Characterized in that the object is an optical disc and the region is a region containing information on the optical disc and / or in the optical disc. A method of identifying an in-focus image of an area on and / or within an object from an out-of-focus image to reduce errors in image information of the object, (a) generating a probe beam and a reference beam from a broadband point source; (b) generating a contrary spatial spatial property to the reference beam; (c) converting the probe beam into a focused beam on an object and / or a line therein; (d) generating an in-focus return probe beam; (e) generating a contrary spatial spatial property to the in-focus return probe beam; (f) spatially filtering the in-focus returning probe beam of step (e); (g) passing a spatially filtered beam through a diffuse element to convert the spatially filtered in-focus return probe beam into a focused beam in a line of the detector plane of the detector system; (h) spatially filtering the reference beam of step (b); (i) passing a spatially filtered reference beam through the discrete element to convert the spatially filtered reference beam into a focused beam in a line of the detector plane of the detector system; (j) spatially filtering the beam from the out-of-focus image point; (k) passing a spatially filtered beam from an out-of-focus image point to the focused image point to convert the beam spatially filtered from the out-of-focus image point into a focused beam on the detector plane step; (l) interfering with the spatially filtered beam from the out-of-focus image point of step (k) and the imaged spatially filtered reference beam of step (i); (m) interfering the focused and spatially filtered in-focus return beam of step (g) with the focused spatially filtered reference beam of step (i); And (f) of said step (i) and of said step (g) by said detector system to reduce errors in data produced by said detector system to represent image information of said object, (Ii) the interference terms between the focused and spatially filtered in-focus return beams, the amplitude of the spatially filtered reference beam of step (i) being substantially reduced and the spatially filtered out- And detecting the amplitude of the interference term between the amplitudes of the focus image beam. 15. The method of claim 14, Wherein the point source is a point on a broadband line source. 15. The method of claim 14, Wherein the object is a semiconductor wafer. 15. The method of claim 14, Characterized in that the object is a biological entity. 15. The method of claim 14, Characterized in that the object is an optical disc and the region is a region containing information on the optical disc and / or in the optical disc. 15. The method of claim 14, Wherein said step (c) comprises passing the probe beam through at least one grating, said line being substantially parallel to the main surface of the object. 15. The method of claim 14, Wherein the line of step (c) is substantially perpendicular to the major surface of the object. 15. The method of claim 14, Further comprising performing a Fourier transform on the data produced by the detector system. An interferometer system for identifying an in-focus image of an area on and / or within an object from an out-of-focus image to reduce errors in the image information of the object, (a) a point source for generating a probe beam and a reference beam; (b) a first phase shifter for generating a contrary spatial spatial characteristic to the reference beam; (c) a first beam guiding device for generating an in-focus return probe beam by directing the probe beam to the in-focus on or within the area; (d) a second phase shifter generating an opposite spatial spatial characteristic to the in-focus return probe beam; (e) a focus return from the out-of-focus image point to the opposite nominal reference beam, and vice versa, to counter the opposite nominal reference beam to the opposite nominal reference beam, A second beam guiding device for guiding the beam; And (f) a detector system for detecting an interference term between a counter-nominal reference beam and an anti-focus return beam, Characterized in that the amplitude of the interference term between the amplitude of the opposing reference beam and the amplitude of the out-of-focus image beam is substantially reduced in order to reduce errors in the data produced by the detector system to represent the image information Interferometer system. 23. The method of claim 22, Wherein the point source is a point of the line source. 23. The method of claim 22, Wherein the point source is a monochromatic point source. 23. The method of claim 22, And the point source is a broadband point source. An interferometer system for identifying an in-focus image of an area on and / or within an object from an out-of-focus image to reduce errors in the image information of the object, (a) a point source for generating a probe beam and a reference beam; (b) a first phase shifter for generating a contrary spatial spatial characteristic to the reference beam; (c) a first beam guiding device for passing the probe beam through a first diaphragm element for converting an in-focus return probe beam into a focused beam on and / or onto an object, and 1 Dispersed element; (d) a second phase shifter generating an opposite spatial spatial characteristic to the in-focus return probe beam; (e) a spatial filter for spatially filtering the anti-symmetric-focus return probe beam; (f) passing a spatially filtered anti-symmetric in-focus return probe beam into a focused beam at the detector plane of the detector system through a second diffuse structured element to convert the spatially filtered anti-symmetric-focused return probe beam into a focused beam at the detector plane of the detector system A second beam guiding device and a second diaphragm element; (g) a spatial filter for spatially filtering the opposite reference beam; (h) a second beam guiding device for passing a spatially filtered counter-symmetry reference beam through the second disparity element to convert the spatially filtered antisymmetric reference beam into a focused beam in the line of the detector plane; (i) a spatial filter for spatially filtering a beam from an out-of-focus image point; (j) a second beam guiding device for passing a spatially filtered beam through a second disparity element to convert the spatially filtered beam from the out-of-focus image point into a beam focused on the detector plane; And (k) a detector system for detecting an interference term between a focused and spatially filtered antisymetric reference beam and a focused and spatially filtered antisymetric-focused return probe beam, The amplitude of the interference term between the magnitude of the focused and spatially filtered antisymmetric reference beam and the amplitude of the focused and spatially filtered out-of-focus image beam is the error of the data produced by the detector system to represent the image of the object Of the interferometer system is reduced substantially. 27. The method of claim 26, Wherein the point source is a point of the line source. 27. The method of claim 26, Wherein the point source is a monochromatic point source. 27. The method of claim 26, And the point source is a broadband point source. An interferometer system for identifying an in-focus image of an area on and / or within an object from an out-of-focus image to reduce errors in the image information of the object, (a) a point source for generating a probe beam and a reference beam; (b) a first phase shifter for generating a contrary spatial spatial characteristic to the reference beam; (c) a focusing device for converting the probe beam into a focused beam on and / or within the object to produce an in-focus return probe beam; (d) a second phase shifter generating an opposite spatial spatial characteristic to the in-focus return probe beam; (e) a spatial filter for spatially filtering the in-focus opposing return probe beam; (f) a beam guide for passing a spatially filtered anti-symmetric in-focus return probe beam through a discoidal element to convert a spatially filtered anti-symmetric-focus return probe beam into a focused beam at a detector plane of the detector system Devices and dispensing elements; (g) a spatial filter for spatially filtering the opposite reference beam; (h) a beam guiding device for passing a spatially filtered counter-symmetrical reference beam through the discrete element to convert the spatially filtered antimagnetic reference beam into a focused beam in the line of the detector plane; (i) a spatial filter for spatially filtering a beam from an out-of-focus image point; (j) a beam guiding device for passing a spatially filtered beam through a second disparity element to convert a spatially filtered beam from an out-of-focus image point into a focused beam in a line of the detector system; And (k) a detector system for detecting an interference term between a focused and spatially filtered antisymetric reference beam and a focused and spatially filtered antisymetric-focused return probe beam, The amplitude of the interference term between the magnitude of the focused and spatially filtered antisymmetric reference beam and the amplitude of the focused and spatially filtered out-of-focus image beam is the error of the data produced by the detector system to represent the image of the object Of the interferometer system is reduced substantially. 31. The method of claim 30, Wherein the point source is a point of the line source. 31. The method of claim 30, And the point source is a broadband point source. A lithographic system for use in the manufacture of integrated circuits on wafers, (a) a stage for supporting a wafer; (b) an illumination system for imaging the spatially patterned radiation on the wafer; (c) a wafer comprising an alignment area on and / or within the wafer; (d) a laser-gauge-controlled positioning system for adjusting the position of the stage with respect to the imaged radiation; And (e) on the object and / or from the out-of-focus image to reduce errors in the image information of the object combined with the laser-gauge-controlled positioning system to measure the state position of the alignment region An interferometric system that identifies the in-focus image of the region. 34. The method of claim 33, Wherein the interferometric system comprises the interferometric system of claim 22. 34. The method of claim 33, Wherein the interferometric system comprises the interferometric system of claim 26. 34. The method of claim 33, Wherein the interferometer system comprises the interferometer system of claim 30. A metrology system for use in inspecting integrated circuit patterns on a wafer during integrated circuit fabrication, (a) a stage for supporting a wafer; (b) a laser-gauge-controlled positioning system for adjusting the relative position of the area on the pattern and / or within the pattern; And (c) an interferometer system for identifying an in-focus image of an area on the pattern and / or within the pattern from the out-of-focus image to reduce errors in the image information of the pattern. system. 39. The method of claim 37, Wherein the interferometer system comprises the interferometer system of claim 22. 39. The method of claim 37, Wherein the interferometer system comprises the interferometer system of claim 26. 39. The method of claim 37, Wherein the interferometer system comprises the interferometer system of claim 30. A metrology system for use in inspecting a pattern in a mask during integrated circuit fabrication, (a) a stage for supporting a wafer; (b) a laser-gauge-controlled positioning system for adjusting the relative position of the area on and / or within the mask; And (c) an interferometer system for identifying an in-focus image of an area on the mask and / or within the mask from an out-of-focus image to reduce errors in the image information of the pattern. system. 42. The method of claim 41, Wherein the interferometer system comprises the interferometer system of claim 22. 42. The method of claim 41, Wherein the interferometer system comprises the interferometer system of claim 26. 42. The method of claim 41, Wherein the interferometer system comprises the interferometer system of claim 30.